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<!DOCTYPE html> <html lang="en" class="grade-c"> <head> <title>Ultrasmall amorphous zirconia nanoparticles catalyse polyolefin hydrogenolysis | Nature Catalysis</title> <link rel="alternate" type="application/rss+xml" href="https://www.nature.com/natcatal.rss"/> <script id="save-data-connection-testing"> function hasConnection() { return navigator.connection || navigator.mozConnection || navigator.webkitConnection || navigator.msConnection; } function createLink(src) { var preloadLink = document.createElement("link"); preloadLink.rel = "preload"; preloadLink.href = src; preloadLink.as = "font"; preloadLink.type = "font/woff2"; preloadLink.crossOrigin = ""; document.head.insertBefore(preloadLink, document.head.firstChild); } var connectionDetail = { saveDataEnabled: false, slowConnection: false }; var connection = hasConnection(); if (connection) { connectionDetail.saveDataEnabled = connection.saveData; if (/\slow-2g|2g/.test(connection.effectiveType)) { connectionDetail.slowConnection = true; } } if (!(connectionDetail.saveDataEnabled || connectionDetail.slowConnection)) { createLink("/static/fonts/HardingText-Regular-Web-cecd90984f.woff2"); } else { document.documentElement.classList.add('save-data'); } </script> <link rel="preconnect" href="https://cmp.nature.com" crossorigin> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="applicable-device" content="pc,mobile"> <meta name="viewport" content="width=device-width,initial-scale=1.0,maximum-scale=5,user-scalable=yes"> <meta name="360-site-verification" content="5a2dc4ab3fcb9b0393241ffbbb490480" /> <script data-test="dataLayer"> window.dataLayer = [{"content":{"category":{"contentType":"article","legacy":{"webtrendsPrimaryArticleType":"research","webtrendsSubjectTerms":"catalytic-mechanisms;heterogeneous-catalysis;sustainability","webtrendsContentCategory":null,"webtrendsContentCollection":null,"webtrendsContentGroup":"Nature Catalysis","webtrendsContentGroupType":null,"webtrendsContentSubGroup":"Article","status":null}},"article":{"doi":"10.1038/s41929-023-00910-x"},"attributes":{"cms":null,"deliveryPlatform":"oscar","copyright":{"open":true,"legacy":{"webtrendsLicenceType":"http://creativecommons.org/licenses/by/4.0/"}}},"contentInfo":{"authors":["Shaojiang Chen","Akalanka Tennakoon","Kyung-Eun You","Alexander L. 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Metal oxides that serve as supports for these catalysts are typically considered to be inert. Here we show that Earth-abundant, non-reducible zirconia catalyses the hydrogenolysis of polyolefins with activity rivalling that of precious metal nanoparticles. To harness this unusual reactivity, our catalytic architecture localizes ultrasmall amorphous zirconia nanoparticles between two fused platelets of mesoporous silica. Macromolecules translocate from bulk through radial mesopores to the highly active zirconia particles, where the chains undergo selective hydrogenolytic cleavage into a narrow, C18-centred distribution. Calculations indicated that C–H bond heterolysis across a Zr–O bond of a Zr(O)2 adatom model for unsaturated surface sites gives a zirconium hydrocarbyl, which cleaves a C–C bond via β-alkyl elimination. \n \n \n \n The cleavage of C–C bonds in hydrocarbons is traditionally entrusted to precious metal catalysts, whereas common non-reducible oxides are considered unreactive. Now, the authors report nanostructured silica-embedded zirconia nanoparticles that are competent for the hydrogenolysis of polyethylene with remarkable performance.","datePublished":"2023-02-16T00:00:00Z","dateModified":"2023-02-16T00:00:00Z","pageStart":"161","pageEnd":"173","license":"http://creativecommons.org/licenses/by/4.0/","sameAs":"https://doi.org/10.1038/s41929-023-00910-x","keywords":["Catalytic mechanisms","Heterogeneous catalysis","Sustainability","Catalysis"],"image":["https://media.springernature.com/lw1200/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Figa_HTML.png","https://media.springernature.com/lw1200/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig1_HTML.png","https://media.springernature.com/lw1200/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig2_HTML.png","https://media.springernature.com/lw1200/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig3_HTML.png","https://media.springernature.com/lw1200/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig4_HTML.png","https://media.springernature.com/lw1200/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig5_HTML.png","https://media.springernature.com/lw1200/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig6_HTML.png"],"isPartOf":{"name":"Nature Catalysis","issn":["2520-1158"],"volumeNumber":"6","@type":["Periodical","PublicationVolume"]},"publisher":{"name":"Nature Publishing Group UK","logo":{"url":"https://www.springernature.com/app-sn/public/images/logo-springernature.png","@type":"ImageObject"},"@type":"Organization"},"author":[{"name":"Shaojiang Chen","url":"http://orcid.org/0000-0002-6952-1010","affiliation":[{"name":"Iowa State University","address":{"name":"US Department of Energy, Ames National Laboratory, Iowa State University, Ames, USA","@type":"PostalAddress"},"@type":"Organization"}],"@type":"Person"},{"name":"Akalanka Tennakoon","url":"http://orcid.org/0000-0001-9897-525X","affiliation":[{"name":"Iowa State University","address":{"name":"US Department of Energy, Ames National Laboratory, Iowa State University, Ames, USA","@type":"PostalAddress"},"@type":"Organization"},{"name":"Iowa State University","address":{"name":"Department of Chemistry, Iowa State University, Ames, USA","@type":"PostalAddress"},"@type":"Organization"}],"@type":"Person"},{"name":"Kyung-Eun You","url":"http://orcid.org/0000-0003-4352-339X","affiliation":[{"name":"University of South Carolina","address":{"name":"Department of Chemical Engineering, University of South Carolina, Columbia, USA","@type":"PostalAddress"},"@type":"Organization"}],"@type":"Person"},{"name":"Alexander L. 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class="c-article-identifiers" data-test="article-identifier"> <li class="c-article-identifiers__item" data-test="article-category">Article</li> <li class="c-article-identifiers__item"> <a href="https://www.springernature.com/gp/open-research/about/the-fundamentals-of-open-access-and-open-research" data-track="click" data-track-action="open access" data-track-label="link" class="u-color-open-access" data-test="open-access">Open access</a> </li> <li class="c-article-identifiers__item">Published: <time datetime="2023-02-16">16 February 2023</time></li> </ul> <h1 class="c-article-title" data-test="article-title" data-article-title="">Ultrasmall amorphous zirconia nanoparticles catalyse polyolefin hydrogenolysis</h1> <ul class="c-article-author-list c-article-author-list--short" data-test="authors-list" data-component-authors-activator="authors-list"><li class="c-article-author-list__item"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Shaojiang-Chen-Aff1" data-author-popup="auth-Shaojiang-Chen-Aff1" data-author-search="Chen, Shaojiang">Shaojiang Chen</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0002-6952-1010"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0002-6952-1010</a></span><sup class="u-js-hide"><a href="#Aff1">1</a></sup><sup class="u-js-hide"> <a href="#na1">na1</a></sup>, </li><li class="c-article-author-list__item"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Akalanka-Tennakoon-Aff1-Aff2" data-author-popup="auth-Akalanka-Tennakoon-Aff1-Aff2" data-author-search="Tennakoon, Akalanka">Akalanka Tennakoon</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0001-9897-525X"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0001-9897-525X</a></span><sup class="u-js-hide"><a href="#Aff1">1</a>,<a href="#Aff2">2</a></sup><sup class="u-js-hide"> <a href="#na1">na1</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Kyung_Eun-You-Aff3" data-author-popup="auth-Kyung_Eun-You-Aff3" data-author-search="You, Kyung-Eun">Kyung-Eun You</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0003-4352-339X"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0003-4352-339X</a></span><sup class="u-js-hide"><a href="#Aff3">3</a></sup><sup class="u-js-hide"> <a href="#na1">na1</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Alexander_L_-Paterson-Aff1" data-author-popup="auth-Alexander_L_-Paterson-Aff1" data-author-search="Paterson, Alexander L.">Alexander L. Paterson</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0002-3069-5910"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0002-3069-5910</a></span><sup class="u-js-hide"><a href="#Aff1">1</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Ryan-Yappert-Aff4" data-author-popup="auth-Ryan-Yappert-Aff4" data-author-search="Yappert, Ryan">Ryan Yappert</a><sup class="u-js-hide"><a href="#Aff4">4</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Selim-Alayoglu-Aff5" data-author-popup="auth-Selim-Alayoglu-Aff5" data-author-search="Alayoglu, Selim">Selim Alayoglu</a><sup class="u-js-hide"><a href="#Aff5">5</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Lingzhe-Fang-Aff6" data-author-popup="auth-Lingzhe-Fang-Aff6" data-author-search="Fang, Lingzhe">Lingzhe Fang</a><sup class="u-js-hide"><a href="#Aff6">6</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Xun-Wu-Aff1-Aff2" data-author-popup="auth-Xun-Wu-Aff1-Aff2" data-author-search="Wu, Xun">Xun Wu</a><sup class="u-js-hide"><a href="#Aff1">1</a>,<a href="#Aff2">2</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Tommy_Yunpu-Zhao-Aff7" data-author-popup="auth-Tommy_Yunpu-Zhao-Aff7" data-author-search="Zhao, Tommy Yunpu">Tommy Yunpu Zhao</a><sup class="u-js-hide"><a href="#Aff7">7</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Michelle_P_-Lapak-Aff7" data-author-popup="auth-Michelle_P_-Lapak-Aff7" data-author-search="Lapak, Michelle P.">Michelle P. Lapak</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0001-7809-3276"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0001-7809-3276</a></span><sup class="u-js-hide"><a href="#Aff7">7</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Mukunth-Saravanan-Aff1" data-author-popup="auth-Mukunth-Saravanan-Aff1" data-author-search="Saravanan, Mukunth">Mukunth Saravanan</a><sup class="u-js-hide"><a href="#Aff1">1</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Ryan_A_-Hackler-Aff8" data-author-popup="auth-Ryan_A_-Hackler-Aff8" data-author-search="Hackler, Ryan A.">Ryan A. Hackler</a><sup class="u-js-hide"><a href="#Aff8">8</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Yi_Yu-Wang-Aff1-Aff2" data-author-popup="auth-Yi_Yu-Wang-Aff1-Aff2" data-author-search="Wang, Yi-Yu">Yi-Yu Wang</a><sup class="u-js-hide"><a href="#Aff1">1</a>,<a href="#Aff2">2</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Long-Qi-Aff1" data-author-popup="auth-Long-Qi-Aff1" data-author-search="Qi, Long">Long Qi</a><sup class="u-js-hide"><a href="#Aff1">1</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Massimiliano-Delferro-Aff8-Aff9" data-author-popup="auth-Massimiliano-Delferro-Aff8-Aff9" data-author-search="Delferro, Massimiliano">Massimiliano Delferro</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0002-4443-165X"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0002-4443-165X</a></span><sup class="u-js-hide"><a href="#Aff8">8</a>,<a href="#Aff9">9</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Tao-Li-Aff6-Aff10" data-author-popup="auth-Tao-Li-Aff6-Aff10" data-author-search="Li, Tao">Tao Li</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0002-4913-4486"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0002-4913-4486</a></span><sup class="u-js-hide"><a href="#Aff6">6</a>,<a href="#Aff10">10</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Byeongdu-Lee-Aff10" data-author-popup="auth-Byeongdu-Lee-Aff10" data-author-search="Lee, Byeongdu">Byeongdu Lee</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0003-2514-8805"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0003-2514-8805</a></span><sup class="u-js-hide"><a href="#Aff10">10</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Baron-Peters-Aff4" data-author-popup="auth-Baron-Peters-Aff4" data-author-search="Peters, Baron">Baron Peters</a><sup class="u-js-hide"><a href="#Aff4">4</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Kenneth_R_-Poeppelmeier-Aff11" data-author-popup="auth-Kenneth_R_-Poeppelmeier-Aff11" data-author-search="Poeppelmeier, Kenneth R.">Kenneth R. Poeppelmeier</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0003-1655-9127"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0003-1655-9127</a></span><sup class="u-js-hide"><a href="#Aff11">11</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Salai_C_-Ammal-Aff3" data-author-popup="auth-Salai_C_-Ammal-Aff3" data-author-search="Ammal, Salai C.">Salai C. Ammal</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0003-0467-1111"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0003-0467-1111</a></span><sup class="u-js-hide"><a href="#Aff3">3</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Clifford_R_-Bowers-Aff7-Aff12" data-author-popup="auth-Clifford_R_-Bowers-Aff7-Aff12" data-author-search="Bowers, Clifford R.">Clifford R. Bowers</a><sup class="u-js-hide"><a href="#Aff7">7</a>,<a href="#Aff12">12</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Fr_d_ric_A_-Perras-Aff1" data-author-popup="auth-Fr_d_ric_A_-Perras-Aff1" data-author-search="Perras, Frédéric A.">Frédéric A. Perras</a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0002-2662-5119"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0002-2662-5119</a></span><sup class="u-js-hide"><a href="#Aff1">1</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Andreas-Heyden-Aff3" data-author-popup="auth-Andreas-Heyden-Aff3" data-author-search="Heyden, Andreas" data-corresp-id="c1">Andreas Heyden<svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-mail-medium"></use></svg></a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0002-4939-7489"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0002-4939-7489</a></span><sup class="u-js-hide"><a href="#Aff3">3</a></sup>, </li><li class="c-article-author-list__item c-article-author-list__item--hide-small-screen"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Aaron_D_-Sadow-Aff1-Aff2" data-author-popup="auth-Aaron_D_-Sadow-Aff1-Aff2" data-author-search="Sadow, Aaron D." data-corresp-id="c2">Aaron D. Sadow<svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-mail-medium"></use></svg></a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0002-9517-1704"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0002-9517-1704</a></span><sup class="u-js-hide"><a href="#Aff1">1</a>,<a href="#Aff2">2</a></sup> & </li><li class="c-article-author-list__show-more" aria-label="Show all 25 authors for this article" title="Show all 25 authors for this article">…</li><li class="c-article-author-list__item"><a data-test="author-name" data-track="click" data-track-action="open author" data-track-label="link" href="#auth-Wenyu-Huang-Aff1-Aff2" data-author-popup="auth-Wenyu-Huang-Aff1-Aff2" data-author-search="Huang, Wenyu" data-corresp-id="c3">Wenyu Huang<svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-mail-medium"></use></svg></a><span class="u-js-hide"> <a class="js-orcid" href="http://orcid.org/0000-0003-2327-7259"><span class="u-visually-hidden">ORCID: </span>orcid.org/0000-0003-2327-7259</a></span><sup class="u-js-hide"><a href="#Aff1">1</a>,<a href="#Aff2">2</a></sup> </li></ul><button aria-expanded="false" class="c-article-author-list__button"><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-down-medium"></use></svg><span>Show authors</span></button> <p class="c-article-info-details" data-container-section="info"> <a data-test="journal-link" href="/natcatal" data-track="click" data-track-action="journal homepage" data-track-category="article body" data-track-label="link"><i data-test="journal-title">Nature Catalysis</i></a> <b data-test="journal-volume"><span class="u-visually-hidden">volume</span> 6</b>, <span class="u-visually-hidden">pages </span>161–173 (<span data-test="article-publication-year">2023</span>)<a href="#citeas" class="c-article-info-details__cite-as u-hide-print" data-track="click" data-track-action="cite this article" data-track-label="link">Cite this article</a> </p> <div class="c-article-metrics-bar__wrapper u-clear-both"> <ul class="c-article-metrics-bar u-list-reset"> <li class=" c-article-metrics-bar__item" data-test="access-count"> <p class="c-article-metrics-bar__count">16k <span class="c-article-metrics-bar__label">Accesses</span></p> </li> <li class="c-article-metrics-bar__item" data-test="altmetric-score"> <p class="c-article-metrics-bar__count">99 <span class="c-article-metrics-bar__label">Altmetric</span></p> </li> <li class="c-article-metrics-bar__item"> <p class="c-article-metrics-bar__details"><a href="/articles/s41929-023-00910-x/metrics" data-track="click" data-track-action="view metrics" data-track-label="link" rel="nofollow">Metrics <span class="u-visually-hidden">details</span></a></p> </li> </ul> </div> </header> <div class="u-js-hide" data-component="article-subject-links"> <h3 class="c-article__sub-heading">Subjects</h3> <ul class="c-article-subject-list"> <li class="c-article-subject-list__subject"><a href="/subjects/catalytic-mechanisms" data-track="click" data-track-action="view subject" data-track-label="link">Catalytic mechanisms</a></li><li class="c-article-subject-list__subject"><a href="/subjects/heterogeneous-catalysis" data-track="click" data-track-action="view subject" data-track-label="link">Heterogeneous catalysis</a></li><li class="c-article-subject-list__subject"><a href="/subjects/sustainability" data-track="click" data-track-action="view subject" data-track-label="link">Sustainability</a></li> </ul> </div> </div> <div class="c-article-body"> <section aria-labelledby="Abs1" data-title="Abstract" lang="en"><div class="c-article-section" id="Abs1-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="Abs1">Abstract</h2><div class="c-article-section__content" id="Abs1-content"><p>Carbon–carbon bond cleavage reactions, adapted to deconstruct aliphatic hydrocarbon polymers and recover the intrinsic energy and carbon value in plastic waste, have typically been catalysed by metal nanoparticles or air-sensitive organometallics. Metal oxides that serve as supports for these catalysts are typically considered to be inert. Here we show that Earth-abundant, non-reducible zirconia catalyses the hydrogenolysis of polyolefins with activity rivalling that of precious metal nanoparticles. To harness this unusual reactivity, our catalytic architecture localizes ultrasmall amorphous zirconia nanoparticles between two fused platelets of mesoporous silica. Macromolecules translocate from bulk through radial mesopores to the highly active zirconia particles, where the chains undergo selective hydrogenolytic cleavage into a narrow, C<sub>18</sub>-centred distribution. Calculations indicated that C–H bond heterolysis across a Zr–O bond of a Zr(O)<sub>2</sub> adatom model for unsaturated surface sites gives a zirconium hydrocarbyl, which cleaves a C–C bond via β-alkyl elimination.</p><div class="c-article-section__figure" data-test="figure" data-container-section="figure"><figure><div class="c-article-section__figure-content"><div class="c-article-section__figure-item"><picture><source type="image/webp" srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Figa_HTML.png?as=webp"><img src="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Figa_HTML.png" alt="" loading="lazy" width="685" height="359"></picture></div></div></figure></div></div></div></section> <noscript> </noscript> <section aria-labelledby="inline-recommendations" data-title="Inline Recommendations" class="c-article-recommendations" data-track-component="inline-recommendations"> <h3 class="c-article-recommendations-title" id="inline-recommendations">Similar content being viewed by others</h3> <div class="c-article-recommendations-list"> <div class="c-article-recommendations-list__item"> <article class="c-article-recommendations-card" itemscope itemtype="http://schema.org/ScholarlyArticle"> <div class="c-article-recommendations-card__img"><img src="https://media.springernature.com/w215h120/springer-static/image/art%3A10.1038%2Fs41467-022-32563-y/MediaObjects/41467_2022_32563_Fig1_HTML.png" loading="lazy" alt=""></div> <div class="c-article-recommendations-card__main"> <h3 class="c-article-recommendations-card__heading" itemprop="name headline"> <a class="c-article-recommendations-card__link" itemprop="url" href="https://www.nature.com/articles/s41467-022-32563-y?fromPaywallRec=false" data-track="select_recommendations_1" data-track-context="inline recommendations" data-track-action="click recommendations inline - 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Active oxides, such as those of molybdenum, tungsten or rhenium, can react with unsaturated hydrocarbons in situ to generate surface alkylidene (M = CR<sub>2</sub>) sites for olefin metathesis<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 1" title="Lwin, S. & Wachs, I. E. Olefin metathesis by supported metal oxide catalysts. ACS Catal. 4, 2505–2520 (2014)." href="/articles/s41929-023-00910-x#ref-CR1" id="ref-link-section-d10980768e1038">1</a></sup>. In contrast, the robust metal oxygen bonds of non-reducible oxides are used to create three-dimensional (3D) architectures, such as in zeolites and mesoporous materials. In catalytic reactions, such materials either make use of acidic or basic surface sites or act as supports for reduced metal nanoparticles, single-atom catalysts or surface organometallic chemistry (SOMC) species, rather than forming metal–carbon bonds themselves. In principle, in situ conversion of non-reducible metal oxides into metal hydride and metal alkyl species, especially in materials with co-localized surface acid sites, could lead to unique multifunctional reaction mechanisms. Such organometalloxide catalysts could be particularly interesting for the selective cleavage of carbon–carbon bonds in hydrocarbons, which has traditionally relied on precious metal-catalysed hydrogenolysis<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Sinfelt, J. H., Taylor, W. F. & Yates, D. J. C. Catalysis over supported metals. III. Comparison of metals of known surface area for ethane hydrogenolysis. J. Phys. Chem. 69, 95–101 (1965)." href="#ref-CR2" id="ref-link-section-d10980768e1042">2</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Gillespie, W. D., Herz, R. K., Petersen, E. E. & Somorjai, G. A. The structure sensitivity of n-heptane dehydrocyclization and hydrogenolysis catalyzed by platinum single crystals at atmospheric pressure. J. Catal. 70, 147–159 (1981)." href="#ref-CR3" id="ref-link-section-d10980768e1042_1">3</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 4" title="Flaherty, D. W. & Iglesia, E. Transition-state enthalpy and entropy effects on reactivity and selectivity in hydrogenolysis of n-alkanes. J. Am. Chem. Soc. 135, 18586–18599 (2013)." href="/articles/s41929-023-00910-x#ref-CR4" id="ref-link-section-d10980768e1045">4</a></sup> or acid-catalysed hydrocracking<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 5" title="Weitkamp, J. Catalytic hydrocracking—mechanisms and versatility of the process. ChemCatChem 4, 292–306 (2012)." href="/articles/s41929-023-00910-x#ref-CR5" id="ref-link-section-d10980768e1049">5</a></sup>. Moreover, developing more effective processes for conversions of hydrocarbon plastics, which are currently used and discarded on a scale of hundreds of megatons<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 6" title="Geyer, R., Jambeck, J. R. & Law, K. L. Production, use, and fate of all plastics ever made. Sci. Adv. 3, e1700782 (2017)." href="/articles/s41929-023-00910-x#ref-CR6" id="ref-link-section-d10980768e1053">6</a></sup>, would also benefit from Earth-abundant oxide-based catalysts.</p><p>The growing global plastic waste crisis<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 7" title="De Smet, M. The New Plastics Economy: Rethinking the Future of Plastics. Report No. 080116 (Ellen Macarthur Foundation, 2016)." href="/articles/s41929-023-00910-x#ref-CR7" id="ref-link-section-d10980768e1060">7</a></sup> has motivated recent studies of supported precious metal nanoparticles as catalysts for hydrogenolysis of polyolefins<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Celik, G. et al. Upcycling single-use polyethylene into high-quality liquid products. ACS Cent. Sci. 5, 1795–1803 (2019)." href="#ref-CR8" id="ref-link-section-d10980768e1064">8</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Liu, S., Kots, P. A., Vance, B. C., Danielson, A. & Vlachos, D. G. Plastic waste to fuels by hydrocracking at mild conditions. Sci. Adv. 7, eabf8283 (2021)." href="#ref-CR9" id="ref-link-section-d10980768e1064_1">9</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Rorrer, J. E., Beckham, G. T. & Román-Leshkov, Y. Conversion of polyolefin waste to liquid alkanes with Ru-based catalysts under mild conditions. JACS Au 1, 8–12 (2021)." href="#ref-CR10" id="ref-link-section-d10980768e1064_2">10</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Nakaji, Y. et al. Low-temperature catalytic upgrading of waste polyolefinic plastics into liquid fuels and waxes. Appl. Catal. B 285, 119805 (2021)." href="#ref-CR11" id="ref-link-section-d10980768e1064_3">11</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 12" title="Jaydev, S. D., Martín, A. J. & Pérez-Ramírez, J. Direct conversion of polypropylene into liquid hydrocarbons on carbon-supported platinum catalysts. ChemSusChem 14, 5179–5185 (2021)." href="/articles/s41929-023-00910-x#ref-CR12" id="ref-link-section-d10980768e1067">12</a></sup>. Carbon–carbon bond cleavage via organozirconium-mediated β-alkyl elimination<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 13" title="O’Reilly, M. E., Dutta, S. & Veige, A. S. β-Alkyl elimination: fundamental principles and some applications. Chem. Rev. 116, 8105–8145 (2016)." href="/articles/s41929-023-00910-x#ref-CR13" id="ref-link-section-d10980768e1071">13</a></sup> has received less attention<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 14" title="Kanbur, U. et al. Catalytic carbon–carbon bond cleavage and carbon–element bond formation give new life for polyolefins as biodegradable surfactants. Chem 7, 1347–1362 (2021)." href="/articles/s41929-023-00910-x#ref-CR14" id="ref-link-section-d10980768e1075">14</a></sup>, despite the Earth abundance of Zr and attractive mild conditions (<150 °C and atmospheric pressure) used for the hydrogenolysis of polyolefins in pioneering work by Dufaud and Basset<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 15" title="Dufaud, V. & Basset, J.-M. Catalytic hydrogenolysis at low temperature and pressure of polyethylene and polypropylene to diesels or lower alkanes by a zirconium hydride supported on silica-alumina: a step toward polyolefin degradation by the microscopic reverse of Ziegler–Natta polymerization. Angew. Chem. Int. Ed. 37, 806–810 (1998)." href="/articles/s41929-023-00910-x#ref-CR15" id="ref-link-section-d10980768e1079">15</a></sup>. The combination of a few of the advantageous features of these distinct classes of catalysts may provide an appropriate strategy for designing organozirconia-mediated hydrogenolysis of hydrocarbons.</p><p>The conventional strategy to achieve high catalytic activity involving evenly dispersed sites over high-surface-area materials has not yet enabled the activation of metal oxides for hydrogenolysis. An alternative catalyst design instead positions active sites at specific isolated locations within a 3D nanosized architecture. In support of this idea, a mesoporous silica shell/platinum catalyst/silica core (mSiO<sub>2</sub>/Pt/SiO<sub>2</sub>) 3D architecture that isolates small Pt nanoparticles at the bottom of mesoporous wells provides high activity and long catalyst lifetimes in polyolefin hydrogenolysis<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 16" title="Tennakoon, A. et al. Catalytic upcycling of high-density polyethylene via a processive mechanism. Nat. Catal. 3, 893–901 (2020)." href="/articles/s41929-023-00910-x#ref-CR16" id="ref-link-section-d10980768e1090">16</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 17" title="Wu, X. et al. Size-controlled nanoparticles embedded in a mesoporous architecture leading to efficient and selective hydrogenolysis of polyolefins. J. Am. Chem. Soc. 144, 5323–5334 (2022)." href="/articles/s41929-023-00910-x#ref-CR17" id="ref-link-section-d10980768e1093">17</a></sup>. In contrast, external-facing platinum in Pt/SiO<sub>2</sub> materials readily deactivates by leaching and sintering. The synthetic methods that localize metal nanoparticles in a 3D architecture, however, are not readily adapted to SOMC zirconium complexes due to their unwanted reactivity with air and moisture, which forces the final synthetic step to be organometallic site installation. In that covalent grafting reaction, the placement of sites is governed by the locations of surface hydroxy groups, which are notoriously difficult to control on metal oxide surfaces<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 18" title="Kobayashi, T., Singappuli-Arachchige, D., Wang, Z., Slowing, I. I. & Pruski, M. Spatial distribution of organic functional groups supported on mesoporous silica nanoparticles: a study by conventional and DNP-enhanced 29Si solid-state NMR. Phys. Chem. Chem. Phys. 19, 1781–1789 (2017)." href="/articles/s41929-023-00910-x#ref-CR18" id="ref-link-section-d10980768e1099">18</a></sup>. Instead, we sought to advance the construction of mixed metal oxide–silica architectures by localizing zirconia particles in a narrow zone within mesoporous silica nanoparticles.</p><p>Metal nanoparticle and SOMC catalysts both benefit from coordinatively unsaturated sites, achieved in metal nanoparticle catalysts through high proportions of edge and corner atoms in small nanoparticles and in SOMC catalysts by immobilization onto inert supports. Although zirconia-catalysed polyolefin hydrogenolysis had not previously been demonstrated, zirconia was shown to catalyse the hydrogenation of alkenes<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 19" title="Kondo, J., Domen, K., Maruya, K.-I. & Onishi, T. Infrared studies of ethene hydrogenation over ZrO2. Part 3.—Reaction mechanism. J. Chem. Soc. Faraday Trans. 88, 2095–2099 (1992)." href="/articles/s41929-023-00910-x#ref-CR19" id="ref-link-section-d10980768e1106">19</a></sup>, and hexane was cracked over zirconia to give similar products and selectivity to the protonated Zeolite Socony Mobil-5 (HZSM-5) acid catalyst<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 20" title="Hoang, D. L. & Lieske, H. Effect of hydrogen treatments on ZrO2 and Pt/ZrO2 catalysts. Catal. Lett. 27, 33–42 (1994)." href="/articles/s41929-023-00910-x#ref-CR20" id="ref-link-section-d10980768e1110">20</a></sup>. Moreover, tests of zirconia as a support for noble metals in hydrogenolysis also suggested its possible activity<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 21" title="Utami, M. et al. Hydrothermal preparation of a platinum-loaded sulphated nanozirconia catalyst for the effective conversion of waste low density polyethylene into gasoline-range hydrocarbons. RSC Adv. 9, 41392–41401 (2019)." href="/articles/s41929-023-00910-x#ref-CR21" id="ref-link-section-d10980768e1114">21</a></sup>. Smaller nanoparticles<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 22" title="Puigdollers, A. R., Tosoni, S. & Pacchioni, G. Turning a nonreducible into a reducible oxide via nanostructuring: opposite behavior of bulk ZrO2 and ZrO2 nanoparticles toward H2 adsorption. J. Phys. Chem. C 120, 15329–15337 (2016)." href="/articles/s41929-023-00910-x#ref-CR22" id="ref-link-section-d10980768e1118">22</a></sup>, the presence of oxygen vacancies<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 20" title="Hoang, D. L. & Lieske, H. Effect of hydrogen treatments on ZrO2 and Pt/ZrO2 catalysts. Catal. Lett. 27, 33–42 (1994)." href="/articles/s41929-023-00910-x#ref-CR20" id="ref-link-section-d10980768e1122">20</a></sup> and undercoordinated sites<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 23" title="Zhang, Y. et al. Control of coordinatively unsaturated Zr sites in ZrO2 for efficient C–H bond activation. Nat. Commun. 9, 3794 (2018)." href="/articles/s41929-023-00910-x#ref-CR23" id="ref-link-section-d10980768e1127">23</a></sup> have also been proposed to enhance the reactivity of zirconia by creating either reducible surface sites or Lewis acid sites<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 24" title="Arce-Ramos, J.-M., Grabow, L. C., Handy, B. E. & Cárdenas-Galindo, M.-G. Nature of acid sites in silica-supported zirconium oxide: a combined experimental and periodic DFT study. J. Phys. Chem. C 119, 15150–15159 (2015)." href="/articles/s41929-023-00910-x#ref-CR24" id="ref-link-section-d10980768e1131">24</a></sup>. Thus, metal oxides with coordinatively unsaturated surface sites in small nanoparticles that are isolated and stabilized by an inert 3D architecture could be promising for carbon–carbon bond hydrogenolysis.</p><p>Herein, we demonstrate that ultrasmall amorphous localized zirconia nanoparticles (L-ZrO<sub>2</sub>), covalently embedded in silica and clamped in a void between two mesoporous platelets (L-ZrO<sub>2</sub>@mSiO<sub>2</sub>), are highly active in the hydrogenolysis of polyethylene. The architecture enhances the catalytic activity of zirconia to become comparable to that of Pt/C and improves its selectivity towards liquid products. Spectroscopic and computational studies implicate heterolytic H–H and C–H bond cleavage steps that generate Zr–H, Zr–C and O–H bonds, indicating that organometallic elementary steps are involved in polymer deconstruction and product formation. From a practical perspective, the catalyst can be handled under ambient conditions and provides a competitive, Earth-abundant and low-cost alternative to precious metal hydrogenolysis catalysts for polyolefin deconstruction.</p></div></div></section><section data-title="Results"><div class="c-article-section" id="Sec2-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="Sec2">Results</h2><div class="c-article-section__content" id="Sec2-content"><h3 class="c-article__sub-heading" id="Sec3">Synthesis and catalyst structure</h3><p>L-ZrO<sub>2</sub>@mSiO<sub>2</sub> was designed for zirconium-catalysed polyolefin deconstruction (Figs.<a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig1"> 1</a> and <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2"> 2</a>). Ultrasmall ZrO<sub><i>x</i></sub>(OH)<sub>4–2<i>x</i></sub> nanoparticles were dispersed on graphene oxide sheets (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">1</a>), mSiO<sub>2</sub> layers were grown on the ZrO<sub><i>x</i></sub>(OH)<sub>4–2<i>x</i></sub>/graphene oxide and the resulting material was washed and calcined to remove structure-directing agents. Inductively coupled plasma mass spectrometry (ICP-MS) analysis of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> revealed a ZrO<sub>2</sub> loading of 4.7 wt% (Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">1</a>). ICP-MS analyses of three batches of as-synthesized L-ZrO<sub>2</sub>@mSiO<sub>2</sub> catalysts (Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">2</a>) ruled out the presence of any other transition metals in the catalyst, including Ru, Rh, Pt, Pd, Au, Re, Os, Ir, Ni, Fe, Co, Cu, Zn, Mo, W, Cd, Ce, Hf, Ti and V. The elemental purity of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> was further supported by X-ray photoelectron spectroscopy (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">2</a>) and energy dispersive X-ray spectroscopy (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">3</a>).</p><div class="c-article-section__figure js-c-reading-companion-figures-item" data-test="figure" data-container-section="figure" id="figure-1" data-title="Construction of L-ZrO2@mSiO2."><figure><figcaption><b id="Fig1" class="c-article-section__figure-caption" data-test="figure-caption-text">Fig. 1: Construction of L-ZrO<sub>2</sub>@mSiO<sub>2</sub>.</b></figcaption><div class="c-article-section__figure-content"><div class="c-article-section__figure-item"><a class="c-article-section__figure-link" data-test="img-link" data-track="click" data-track-label="image" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/1" rel="nofollow"><picture><source type="image/webp" srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig1_HTML.png?as=webp"><img aria-describedby="Fig1" src="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig1_HTML.png" alt="figure 1" loading="lazy" width="685" height="129"></picture></a></div><div class="c-article-section__figure-description" data-test="bottom-caption" id="figure-1-desc"><p>The construction of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> involves three steps: (1) precipitation–deposition of ZrO<sub><i>x</i></sub>(OH)<sub>4–2<i>x</i></sub> nanoparticles onto graphene oxide, (2a) coating of mSiO<sub>2</sub> onto ZrO<sub><i>x</i></sub>(OH)<sub>4–2<i>x</i></sub>/graphene oxide and (2b) calcination at 550 °C.</p></div></div><div class="u-text-right u-hide-print"><a class="c-article__pill-button" data-test="article-link" data-track="click" data-track-label="button" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/1" data-track-dest="link:Figure1 Full size image" aria-label="Full size image figure 1" rel="nofollow"><span>Full size image</span><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-right-small"></use></svg></a></div></figure></div><div class="c-article-section__figure js-c-reading-companion-figures-item" data-test="figure" data-container-section="figure" id="figure-2" data-title="Electron microscopy and X-ray absorption spectroscopy for ZrO2 catalyst characterization."><figure><figcaption><b id="Fig2" class="c-article-section__figure-caption" data-test="figure-caption-text">Fig. 2: Electron microscopy and X-ray absorption spectroscopy for ZrO<sub>2</sub> catalyst characterization.</b></figcaption><div class="c-article-section__figure-content"><div class="c-article-section__figure-item"><a class="c-article-section__figure-link" data-test="img-link" data-track="click" data-track-label="image" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/2" rel="nofollow"><picture><source type="image/webp" srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig2_HTML.png?as=webp"><img aria-describedby="Fig2" src="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig2_HTML.png" alt="figure 2" loading="lazy" width="685" height="744"></picture></a></div><div class="c-article-section__figure-description" data-test="bottom-caption" id="figure-2-desc"><p><b>a</b>,<b>b</b>, Low-magnification (<b>a</b>) and high-magnification (<b>b</b>) high-angle annular dark-field (HAADF) STEM images of L-ZrO<sub>2</sub>@mSiO<sub>2</sub>. Inset in <b>a</b>, selected area electron diffraction pattern. <b>c</b>,<b>d</b>, Low-magnification (<b>c</b>) and high-resolution (<b>d</b>) HAADF STEM images of the cross-section of an L-ZrO<sub>2</sub>@mSiO<sub>2</sub> particle prepared by microtomy. <b>e</b>,<b>f</b>, High-magnification HAADF STEM image (<b>e</b>) and corresponding energy dispersive X-ray spectroscopy elemental (top left, Si and Zr; top right, Si; bottom left, O; bottom right, Zr) maps (<b>f</b>) of the cross-section of an L-ZrO<sub>2</sub>@mSiO<sub>2</sub> particle. <b>g</b>,<b>h</b>, Normalized Zr <i>k</i>-edge X-ray absorption near-edge structure spectra (<b>g</b>) and <i>k</i><sub>2</sub>-weighted EXAFS spectra (<b>h</b>) of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> and control samples. Inset in <b>g</b>, first derivative spectra.</p></div></div><div class="u-text-right u-hide-print"><a class="c-article__pill-button" data-test="article-link" data-track="click" data-track-label="button" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/2" data-track-dest="link:Figure2 Full size image" aria-label="Full size image figure 2" rel="nofollow"><span>Full size image</span><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-right-small"></use></svg></a></div></figure></div><p>The performance of L-ZrO<sub>2</sub>@SiO<sub>2</sub> is best understood through comparisons with the behaviour of several reference catalysts, whose relevant structures are briefly described here and summarized in Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">1</a>. mSiO<sub>2</sub>, synthesized by templated silica growth on graphene oxide<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 25" title="Yang, S. et al. Graphene-based nanosheets with a sandwich. Struct. Angew. Chem. Int. Ed. 49, 4795–4799 (2010)." href="/articles/s41929-023-00910-x#ref-CR25" id="ref-link-section-d10980768e1384">25</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 26" title="Wang, Z.-M., Wang, W., Coombs, N., Soheilnia, N. & Ozin, G. A. Graphene oxide–periodic mesoporous silica sandwich nanocomposites with vertically oriented channels. ACS Nano 4, 7437–7450 (2010)." href="/articles/s41929-023-00910-x#ref-CR26" id="ref-link-section-d10980768e1387">26</a></sup>, has the same layered platelet morphology and porous structure (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">4</a>) as L-ZrO<sub>2</sub>@mSiO<sub>2</sub>. Imp-ZrO<sub>2</sub>/mSiO<sub>2</sub>, produced by incipient wetness impregnation of zirconium precursors into mSiO<sub>2</sub>, contains randomly dispersed amorphous ZrO<sub>2</sub> nanoparticles (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">5</a>). ZrO<sub>2</sub>-6/mSiO<sub>2</sub> was prepared by immobilizing pre-synthesized 6 nm monoclinic ZrO<sub>2</sub> nanoparticles (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">6</a>) on the external surface of mSiO<sub>2</sub> (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">7</a>). ZrO<sub>2</sub>-30 and Pt/C are, respectively, commercial monoclinic zirconia (~30 nm in size) and platinum nanoparticles supported on carbon (1.3 ± 0.4 nm in size) (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">8</a>). L-Pt@mSiO<sub>2</sub> (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">9</a>), synthesized by deposition of PtO<sub><i>x</i></sub>(OH)<sub>4–2<i>x</i></sub> nanoparticles on graphene oxide (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">10</a>) followed by growth of the mSiO<sub>2</sub> shell, creates a comparable architecture to L-ZrO<sub>2</sub>@mSiO<sub>2</sub> with 3.5 ± 0.8 nm platinum nanoparticles instead of zirconia. The total surface area and Barrett–Joyner–Halenda pore size for mSiO<sub>2</sub>-based samples are ~900–1,000 m<sup>2</sup> g<sup>−1</sup> and 3.4–3.8 nm, respectively (Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">1</a>).</p><p>The low-magnification scanning transmission electron microscopy (STEM) image (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2a</a>) of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> showed its separated nanoplatelet particle morphology, with lateral dimensions ranging from hundreds of nanometres to a few micrometres. Pore diameters of 3.4 ± 0.4 nm in the mesoporous silica nanoplatelets, as revealed by the higher-magnification image (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2b</a>), matched the values obtained with N<sub>2</sub> sorption isotherm measurements (Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">1</a> and Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">11</a>). Notably, the STEM images of cross-sectioned L-ZrO<sub>2</sub>@mSiO<sub>2</sub> particles, prepared with an ultramicrotome (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2c–e</a>), clearly showed a thin (~3 nm) bright band, as was identified by elemental mapping as a region of concentrated zirconium (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2f</a>), between the two 35-nm-thick sheets of mSiO<sub>2</sub>. The mesopores in mSiO<sub>2</sub> are aligned perpendicular to the nanoplate (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2e</a>)<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 26" title="Wang, Z.-M., Wang, W., Coombs, N., Soheilnia, N. & Ozin, G. A. Graphene oxide–periodic mesoporous silica sandwich nanocomposites with vertically oriented channels. ACS Nano 4, 7437–7450 (2010)." href="/articles/s41929-023-00910-x#ref-CR26" id="ref-link-section-d10980768e1505">26</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 27" title="Wang, Z.-M. et al. Sandwich-type nanocomposite of reduced graphene oxide and periodic mesoporous silica with vertically aligned mesochannels of tunable pore depth and size. Adv. Func. Mater. 27, 1704066 (2017)." href="/articles/s41929-023-00910-x#ref-CR27" id="ref-link-section-d10980768e1508">27</a></sup>, and the diameter of the ZrO<sub>2</sub> particles is 3.0 ± 0.5 nm (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">12</a>).</p><p>The amorphous nature and chemical structure of the ultrasmall ZrO<sub>2</sub> nanoparticles in L-ZrO<sub>2</sub>@mSiO<sub>2</sub> were established by electron diffraction, powder X-ray diffraction, X-ray absorption spectroscopy and solid-state nuclear magnetic resonance (NMR) spectroscopy. A diffuse ring in the selected area electron diffraction pattern (inset in Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2a</a>) indicated amorphous characteristics of the material, in contrast with the sharp diffraction spots or rings typical of crystalline substances. The high-resolution image (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2d</a>) further revealed that both ZrO<sub>2</sub> and mSiO<sub>2</sub> lack long-range order. Diffraction peaks from ZrO<sub>2</sub> were not detected in the powder X-ray diffraction pattern of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">13</a>). The strong pre-edge peak in X-ray absorption near-edge structure spectra (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2g</a>) and the same peak intensity in Fourier-transformed extended X-ray absorption fine-structure (EXAFS) spectra (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig2">2h</a>) for the Zr–O distance in all ZrO<sub>2</sub> samples confirmed that Zr is in the +4 oxidation state. The non-crystalline nature of ZrO<sub>2</sub> in L-ZrO<sub>2</sub>@mSiO<sub>2</sub> was distinguished by EXAFS from crystalline ZrO<sub>2</sub>-6/mSiO<sub>2</sub> and ZrO<sub>2</sub>-30, which contained a Zr–Zr scattering path at 2.9 Å.</p><p>The direct (<i>e</i> → <sup>17</sup>O) dynamic nuclear polarization (DNP) surface-enhanced (SENS)<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 28" title="Lesage, A. et al. Surface enhanced NMR spectroscopy by dynamic nuclear polarization. J. Am. Chem. Soc. 132, 15459–15461 (2010)." href="/articles/s41929-023-00910-x#ref-CR28" id="ref-link-section-d10980768e1577">28</a></sup> magic angle spinning (MAS) <sup>17</sup>O Hahn echo NMR spectrum of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig3">3a</a>) contained a broadened, axially symmetric, quadrupolar powder pattern with an isotropic chemical shift of 50 ppm and a quadrupolar coupling constant of 5 MHz, assigned to siloxane linkages. To aid in the assignment of additional broad signals at 400 and 150 ppm at 9.4 T, probably attributable to the ZrO<sub>2</sub> nanoparticles, we acquired DNP SENS data on pure monoclinic ZrO<sub>2</sub> nanoparticles (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig3">3b</a>). ZrO<sub>2</sub>-30 gave rise to sharp resonances at 325 and 402 ppm from μ<sup>4</sup>-O<sup>2–</sup> and μ<sup>3</sup>-O<sup>2–</sup> lattice sites<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 29" title="Shen, L. et al. 17O solid-state NMR studies of ZrO2 nanoparticles. J. Phys. Chem. C 123, 4158–4167 (2019)." href="/articles/s41929-023-00910-x#ref-CR29" id="ref-link-section-d10980768e1609">29</a></sup> and a broad resonance from approximately 425–300 ppm from surface μ<sup>3</sup>- and μ<sup>4</sup>-O<sup>2–</sup> sites. The resonance at 400 ppm in the <sup>17</sup>O Hahn echo spectrum of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> was assigned to disordered surface Zr oxide sites. In addition, the sharp signals from the crystalline ZrO<sub>2</sub> phase contrasted the broad resonances from L-ZrO<sub>2</sub>@mSiO<sub>2</sub>, further supporting the conclusion that the ZrO<sub>2</sub> particles are amorphous. We further performed indirect (<i>e</i> → <sup>1</sup>H → <sup>17</sup>O) DNP SENS experiments to assign the resonance at 150 ppm in L-ZrO<sub>2</sub>@mSiO<sub>2</sub>, using phase-shifted recoupling effects a smooth transfer of order (PRESTO) experiments to acquire the <sup>17</sup>O MAS NMR spectra of only the hydroxy species<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 30" title="Perras, F. A., Kobayashi, T. & Pruski, M. Natural abundance 17O DNP two-dimensional and surface-enhanced NMR spectroscopy. J. Am. Chem. Soc. 137, 8336–8339 (2015)." href="/articles/s41929-023-00910-x#ref-CR30" id="ref-link-section-d10980768e1649">30</a></sup>. The PRESTO spectrum of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig3">3c</a>) was dominated by a previously obscured resonance at approximately –50 ppm assigned to surface silanols. Alternatively, the spectrum of ZrO<sub>2</sub>-30 contained a signal at approximately 150 ppm at 9.4 T (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig3">3d</a>), which was unambiguously assigned to Zr–OH sites<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 29" title="Shen, L. et al. 17O solid-state NMR studies of ZrO2 nanoparticles. J. Phys. Chem. C 123, 4158–4167 (2019)." href="/articles/s41929-023-00910-x#ref-CR29" id="ref-link-section-d10980768e1666">29</a></sup>.<sup>,</sup> The contrast between the spectra of the two samples suggests that a dominant component of the resonance at 150 ppm in the <sup>17</sup>O Hahn echo spectrum of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> is not a Zr–OH species but rather Si–O–Zr linkages. We observed such a site in a previous study of a Zr(NMe<sub>2</sub>)<sub>3</sub>/SiO<sub>2</sub> species where it resonated at 146 ppm at 9.4 T<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 31" title="Perras, F. A., Boteju, K. C., Slowing, I. I., Sadow, A. D. & Pruski, M. Direct 17O dynamic nuclear polarization of single-site heterogeneous catalysts. Chem. Commun. 54, 3472–3475 (2018)." href="/articles/s41929-023-00910-x#ref-CR31" id="ref-link-section-d10980768e1685">31</a></sup>. Importantly, the observation of this resonance confirms that the silica and zirconia phases are covalently linked to one another.</p><div class="c-article-section__figure js-c-reading-companion-figures-item" data-test="figure" data-container-section="figure" id="figure-3" data-title="Solid-state NMR spectra of ZrO2 catalysts."><figure><figcaption><b id="Fig3" class="c-article-section__figure-caption" data-test="figure-caption-text">Fig. 3: Solid-state NMR spectra of ZrO<sub>2</sub> catalysts.</b></figcaption><div class="c-article-section__figure-content"><div class="c-article-section__figure-item"><a class="c-article-section__figure-link" data-test="img-link" data-track="click" data-track-label="image" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/3" rel="nofollow"><picture><img aria-describedby="Fig3" src="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig3_HTML.png" alt="figure 3" loading="lazy" width="685" height="569"></picture></a></div><div class="c-article-section__figure-description" data-test="bottom-caption" id="figure-3-desc"><p><b>a</b>,<b>b</b>, Direct DNP-enhanced <sup>17</sup>O Hahn echo spectra of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> (<b>a</b>) and monoclinic ZrO<sub>2</sub>-30 nanoparticles (<b>b</b>). <b>c</b>,<b>d</b>, Indirect DNP-enhanced <sup>17</sup>O{<sup>1</sup>H} PRESTO NMR spectra of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> (<b>c</b>) and ZrO<sub>2</sub>-30 nanoparticles (<b>d</b>). All of the data were acquired at a MAS rate of 14 kHz. Spinning sidebands are indicated by asterisks. Crystalline sites are further labelled by daggers.</p></div></div><div class="u-text-right u-hide-print"><a class="c-article__pill-button" data-test="article-link" data-track="click" data-track-label="button" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/3" data-track-dest="link:Figure3 Full size image" aria-label="Full size image figure 3" rel="nofollow"><span>Full size image</span><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-right-small"></use></svg></a></div></figure></div><p>The thermochemical stability of ZrO<sub>2</sub> is affected by the mSiO<sub>2</sub> shell. Calcination of ZrO<sub><i>x</i></sub>(OH)<sub>4–2<i>x</i></sub>/graphene oxide at 550 °C formed a mixture of tetragonal and monoclinic ZrO<sub>2</sub> nanocrystals (Scherrer size = 5.5 and 9.3 nm, respectively; Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">14</a>). Similar calcination of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> did not provide detectable signals of crystalline domains (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">13</a>). It is likely that the confinement of ultrasmall ZrO<sub>2</sub> nanoparticles within the mesopores, along with the covalent Si–O–Zr bonding, limits their growth and crystallization.</p><h3 class="c-article__sub-heading" id="Sec4">Polymer deconstruction catalysis</h3><p>Polyethylene hydrogenolysis was performed with ~3 g melted polyethylene (number-averaged molecular mass (<i>M</i><sub>n</sub>) = 20 kDa and weight-averaged molecular mass (<i>M</i><sub>w</sub>) = 91 kDa; Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">16</a>) and 5.5 mg catalyst under 0.992 MPa of H<sub>2</sub> at 300 °C as the standard conditions. The high mass-specific catalytic activity of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> was established by the rate of C–C bonds cleaved per metal mass (2.3 ± 0.4 mol H<sub>2</sub> (g Zr)<sup>–1</sup> h<sup>–1</sup>). The number of C–C bonds that were broken in each experiment was determined by measuring the consumption of H<sub>2</sub> (each H<sub>2</sub> molecule consumed corresponds to one hydrogenolysed C–C bond) and comparing starting and final total molecular weight distributions (<i>M</i><sub>n</sub>) of the entire sample, including the C<sub>1</sub>–C<sub>9</sub> species in the reactor headspace, the C<sub>8</sub>–C<sub>50</sub> liquid and wax fraction extracted with dichloromethane and the >C<sub>50</sub> polymeric solid residue (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig4">4a,b</a> and Supplementary Tables <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">3</a> and <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">6</a>). The <i>M</i><sub>n</sub> versus time curve followed the generally expected decay (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">15</a>).</p><div class="c-article-section__figure js-c-reading-companion-figures-item" data-test="figure" data-container-section="figure" id="figure-4" data-title="Hydrogenolysis results from L-ZrO2@mSiO2 and control catalysts."><figure><figcaption><b id="Fig4" class="c-article-section__figure-caption" data-test="figure-caption-text">Fig. 4: Hydrogenolysis results from L-ZrO<sub>2</sub>@mSiO<sub>2</sub> and control catalysts.</b></figcaption><div class="c-article-section__figure-content"><div class="c-article-section__figure-item"><a class="c-article-section__figure-link" data-test="img-link" data-track="click" data-track-label="image" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/4" rel="nofollow"><picture><source type="image/webp" srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig4_HTML.png?as=webp"><img aria-describedby="Fig4" src="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig4_HTML.png" alt="figure 4" loading="lazy" width="685" height="667"></picture></a></div><div class="c-article-section__figure-description" data-test="bottom-caption" id="figure-4-desc"><p><b>a</b>, Time-dependent conversion of polyethylene (<i>M</i><sub>n</sub> = 20 kDa; <i>M</i><sub>w</sub> = 90 kDa; <i>Ð</i> = 4.8), liquid yield and volatile yield, in mass percentage, catalysed by L-ZrO<sub>2</sub>@mSiO<sub>2</sub> under H<sub>2</sub> at 300 °C. The data are presented as H<sub>2</sub> quantification (means ± 1σ), as determined from three or more gas chromatography measurements. <b>b</b>, Carbon number distribution of liquid products from the hydrogenolysis of polyethylene catalysed by L-ZrO<sub>2</sub>@mSiO<sub>2</sub> after 2, 4, 6, 8, 12 and 20 h. <b>c</b>, Comparison of C–C bond cleavage activity (left axis, hashed bars, mean ± 1σ, as determined from three H<sub>2</sub> quantification measurements and the mass of metal loading) and conversion of polyethylene (PE; right axis, open bars, mean ± 1σ, as determined from two experiments of isolated material) at 300 °C for 6 h. <b>d</b>, Comparison of C–C bond cleavage reactivity for short, long, and ultra-high-molecular-weight high-density polyethylene (UHMWPE), as well as linear and branched polymers in L-ZrO<sub>2</sub>@mSiO<sub>2</sub>-catalysed hydrogenolysisσ (mean ± 1σ). <b>e</b>, Carbon number distribution of liquid products catalysed by L-ZrO<sub>2</sub>@mSiO<sub>2</sub>, ZrO<sub>2</sub>-30, Imp-ZrO<sub>2</sub>/mSiO<sub>2</sub> and ZrO<sub>2</sub>-6/mSiO<sub>2</sub>, obtained from reactions that consumed similar moles of H<sub>2</sub>.</p><p><a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM2">Source data</a></p></div></div><div class="u-text-right u-hide-print"><a class="c-article__pill-button" data-test="article-link" data-track="click" data-track-label="button" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/4" data-track-dest="link:Figure4 Full size image" aria-label="Full size image figure 4" rel="nofollow"><span>Full size image</span><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-right-small"></use></svg></a></div></figure></div><p>A few zirconia materials show catalytic activity in polyethylene hydrogenolysis, with L-ZrO<sub>2</sub>@mSiO<sub>2</sub> providing the highest conversion of polyethylene and high mass-specific activity for C–C bond breakage (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig4">4c</a>). Its activity for C–C bond cleavage is ~23 ± 2× and 2.4 ± 0.3× higher than the activities of ZrO<sub>2</sub>-30 and ZrO<sub>2</sub>-6/mSiO<sub>2</sub>, and comparable to that of Imp-ZrO<sub>2</sub>/mSiO<sub>2</sub> (Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">6</a>). Remarkably, the activity of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> for C–C cleavage is even competitive with that of Pt-based catalysts following the trend L-ZrO<sub>2</sub>@mSiO<sub>2</sub> ~ Pt/C < L-Pt@mSiO<sub>2</sub>. The similar activity of Pt and confined Zr, along with the <0.001 wt% concentration of other transition metals measured by ICP-MS of as-synthesized and post-reaction zirconia catalysts, as well as catalyst-free control experiments, also ruled out trace contaminants as being catalytically important species.</p><p>The L-ZrO<sub>2</sub>@mSiO<sub>2</sub>-catalysed polyethylene hydrogenolysis produced a narrow, Gaussian-type C<sub>18</sub>-centred distribution of liquid hydrocarbons, with C<sub>9</sub>–C<sub>27</sub> representing >90% of the chains. This characteristic distribution was formed at the initial stage of the reaction and increased in yield in a roughly linear fashion until ~75% polyethylene conversion (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig4">4a,b</a> and Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">3</a>). The volatile species, which represented the low-end tail of the product distribution, similarly increased in yield as the reaction progressed (Supplementary Figs. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">20</a>–<a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">44</a>). After >80% conversion of the polyethylene, the average chain length in the liquid products decreased to C<sub>16</sub> after 15 h (Supplementary Figs. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">47</a> and<a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1"> 48</a>) and sharpened after 20 h (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig4">4b</a>), and the weight fraction of volatile products, mostly composed of methane and ethane, further increased (Supplementary Figs. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">45</a>–<a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">53</a>). We attribute these observations to the secondary hydrogenolysis of the C<sub>18</sub>-centred distribution that occurred primarily at the ends of the chains. These results further indicate that L-ZrO<sub>2</sub>@mSiO<sub>2</sub>-catalysed hydrogenolysis is selective for the long hydrocarbon chains of polyethylene rather than the shorter chains of the primary products. This remarkable behaviour resembles mSiO<sub>2</sub>/Pt/SiO<sub>2</sub>-catalysed hydrogenolysis of polyethylene<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 16" title="Tennakoon, A. et al. Catalytic upcycling of high-density polyethylene via a processive mechanism. Nat. Catal. 3, 893–901 (2020)." href="/articles/s41929-023-00910-x#ref-CR16" id="ref-link-section-d10980768e2038">16</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 17" title="Wu, X. et al. Size-controlled nanoparticles embedded in a mesoporous architecture leading to efficient and selective hydrogenolysis of polyolefins. J. Am. Chem. Soc. 144, 5323–5334 (2022)." href="/articles/s41929-023-00910-x#ref-CR17" id="ref-link-section-d10980768e2041">17</a></sup> and contrasts with the performance of the other ZrO<sub>2</sub> catalysts, which give broader, non-Gaussian or multimodal distributions (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig4">4e</a>), which also vary throughout the polyethylene conversion (Supplementary Tables <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">4</a> and <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">6</a> and Supplementary Figs. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">54</a>–<a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">87</a>).</p><p>This highly disperse polyethylene (<i>M</i><sub>n</sub> = 20 kDa) represents the typical range used for flexible packaging applications. Accordingly, L-ZrO<sub>2</sub>@mSiO<sub>2</sub>-catalysed hydrogenolysis of a post-consumer low-density polyethylene (LDPE) grocery bag (<i>M</i><sub>n</sub> = 10.6 kDa and <i>M</i><sub>w</sub> = 150 kDa; dried under vacuum; Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">18</a>) resulted in equivalent reactivity (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig4">4d</a>; 2.3 ± 0.4 mol H<sub>2</sub>(g Zr)<sup>–1</sup> h<sup>–1</sup>). The catalytic activity was also similar for hexatriacontane (<i>n</i>-C<sub>36</sub>H<sub>74</sub>), LDPE (<i>M</i><sub>n</sub> = 2.8 kDa and <i>M</i><sub>w</sub> = 5.3 kDa; Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">17</a>) and ultra-high-molecular-weight high-density polyethylene (<i>M</i><sub>w</sub> = ~3,000–5,000 kDa). These results suggest that rates of threading of chains into pores and translocation to the active sites at the ends of the pores are not limiting the rates of C–C bond cleavage for short and long chains as well as branched and linear polymers, and the distribution is independent of the C–C bond cleavage rate; however, the conformations of long and short chains probably vary to influence the distributions. Specifically, hydrogenolysis of hexatriacontane provided a distribution of chain end-cleaved hydrocarbons, similar to the process observed for secondary hydrogenolysis of C<sub>18</sub> primary products noted above. In contrast, ultra-high-molecular-weight high-density polyethylene or post-consumer LDPE gave broad distributions, respectively (Supplementary Figs. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">88</a>–<a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">103</a>). In addition, L-ZrO<sub>2</sub>@mSiO<sub>2</sub> produced a narrower distribution of chain lengths of extractable species compared with the other ZrO<sub>2</sub>-based catalysts at a similar polyethylene conversion (39–54%; Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig4">4e</a>).</p><h3 class="c-article__sub-heading" id="Sec5">Mechanistic analysis</h3><p>The amorphous ZrO<sub>2</sub> nanoparticles in L-ZrO<sub>2</sub>@mSiO<sub>2</sub>, leading to low-coordinated metal ions<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Petkov, V., Holzhüter, G., Tröge, U., Gerber, T. & Himmel, B. Atomic-scale structure of amorphous TiO2 by electron, X-ray diffraction and reverse Monte Carlo simulations. J. Non. Cryst. Solids 231, 17–30 (1998)." href="#ref-CR32" id="ref-link-section-d10980768e2151">32</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Lee, S. K., Lee, S. B., Park, S. Y., Yi, Y. S. & Ahn, C. W. Structure of amorphous aluminum oxide. Phys. Rev. Lett. 103, 095501 (2009)." href="#ref-CR33" id="ref-link-section-d10980768e2151_1">33</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" title="Buchholz, D. B. et al. The structure and properties of amorphous indium oxide. Chem. Mater. 26, 5401–5411 (2014)." href="#ref-CR34" id="ref-link-section-d10980768e2151_2">34</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 35" title="Strand, J. et al. Intrinsic charge trapping in amorphous oxide films: status and challenges. J. Phys. Condens. Matter 30, 233001 (2018)." href="/articles/s41929-023-00910-x#ref-CR35" id="ref-link-section-d10980768e2154">35</a></sup>, were modelled by a Zr adatom supported on a (–111) surface of monoclinic ZrO<sub>2</sub> (Zr/ZrO<sub>2</sub>). A constrained ab initio thermodynamic analysis of 21 structures (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">106</a> and Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">9</a>) with varying numbers of H, O and OH groups adsorbed on the Zr atom identified Zr(O)<sub>2</sub>/ZrO<sub>2</sub> as the lowest energy of a possible adatom species with reference to Zr/m-ZrO<sub>2</sub>, gas-phase H<sub>2</sub> and trace H<sub>2</sub>O (<b>a0</b> in Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig5">5</a>; Δ<i>G</i> = –3.41 eV; <i>T</i> = 300 °C; <span class="mathjax-tex">$P_{{\rm{H}}_{2}}$</span> = 0.90 MPa; <span class="mathjax-tex">$P_{{\rm{H}}_{2}{\rm{O}}}$</span> = 6.89 × 10<sup>−15</sup> MPa). In Zr(O)<sub>2</sub>/ZrO<sub>2</sub>, the Zr adatom is bonded to two oxo species with short Zr–O interatomic distances (1.92 and 1.97 Å) and coordinated by surface oxygen donors with longer Zr–O distances. The oxo species are also bridged to the Zr of the support. The resulting electron-deficient, low-coordinate Zr species are representative of adatom, corner and edge sites that are expected to be widely present in the amorphous ZrO<sub>2</sub> nanoparticles. The Zr(O)<sub>2</sub>/ZrO<sub>2</sub> species reacts with H<sub>2</sub> via heterolytic dissociation, leading to HZr(OH)(O)/ZrO<sub>2</sub> (Δ<i>G</i> = –3.34 eV; <b>b0</b> in Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig5">5</a> and Supplementary Table <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">9</a>).</p><div class="c-article-section__figure js-c-reading-companion-figures-item" data-test="figure" data-container-section="figure" id="figure-5" data-title="Calculated bond activation by ZrO2."><figure><figcaption><b id="Fig5" class="c-article-section__figure-caption" data-test="figure-caption-text">Fig. 5: Calculated bond activation by ZrO<sub>2</sub>.</b></figcaption><div class="c-article-section__figure-content"><div class="c-article-section__figure-item"><a class="c-article-section__figure-link" data-test="img-link" data-track="click" data-track-label="image" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/5" rel="nofollow"><picture><source type="image/webp" srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig5_HTML.png?as=webp"><img aria-describedby="Fig5" src="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig5_HTML.png" alt="figure 5" loading="lazy" width="685" height="1128"></picture></a></div><div class="c-article-section__figure-description" data-test="bottom-caption" id="figure-5-desc"><p>Side views of the optimized structures of intermediates and transition states (TS) corresponding to the initial C–H bond activation of hexane over Zr(O)<sub>2</sub>/ZrO<sub>2</sub> (<b>a0</b>) and HZr(OH)(O)/ZrO<sub>2</sub> (<b>b0</b>) adatom models, both forming H<sub>13</sub>C<sub>6</sub>Zr(OH)(O)/ZrO<sub>2</sub> (<b>a2</b>). Distances are given in Å.</p></div></div><div class="u-text-right u-hide-print"><a class="c-article__pill-button" data-test="article-link" data-track="click" data-track-label="button" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/5" data-track-dest="link:Figure5 Full size image" aria-label="Full size image figure 5" rel="nofollow"><span>Full size image</span><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-right-small"></use></svg></a></div></figure></div><p>This heterolytic dissociation of H<sub>2</sub> on L-ZrO<sub>2</sub>@mSiO<sub>2</sub> was supported by in situ diffuse reflectance infrared Fourier transform spectroscopy experiments under flowing H<sub>2</sub> at 300 °C, which revealed a small peak at 1,547 cm<sup>−1</sup>, bands at 3,731 and 1,613 cm<sup>−1</sup> and a broad feature at 3,600–3,100 cm<sup>−1</sup> (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">104</a>). The signal at 1,547 cm<sup>−1</sup> disappeared upon flowing D<sub>2</sub>; however, the expected band at ~1,100 cm<sup>–1</sup> was not detected above the strong silica absorption (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">105</a>). The peak intensities at 3,730 and 3,600–3,100 cm<sup>−1</sup> also diminished under D<sub>2</sub>, and signals appeared at 2,700 and 2,600–2,300 cm<sup>−1</sup>. These signals disappeared and the original features reappeared upon flowing H<sub>2</sub>. On the basis of this H/D exchange behaviour and reported assignments<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 36" title="Onishi, T., Abe, H., Maruya, K.-I. & Domen, K. IR spectra of hydrogen adsorbed on ZrO2. J. Chem. Soc. Chem. Commun. 1985, 617–618 (1985)." href="/articles/s41929-023-00910-x#ref-CR36" id="ref-link-section-d10980768e2390">36</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 37" title="Hicks, K. E. et al. Zr6O8 node-catalyzed butene hydrogenation and isomerization in the metal–organic framework NU-1000. ACS Catal. 10, 14959–14970 (2020)." href="/articles/s41929-023-00910-x#ref-CR37" id="ref-link-section-d10980768e2393">37</a></sup>, the band at 1,547 cm<sup>−1</sup> was assigned to <i>ν</i><sub>ZrH</sub> and the other signals were attributed to <i>ν</i><sub>OH</sub> from SiOH and ZrOH, providing experimental support for the idea of heterolytic dissociative adsorption of H<sub>2</sub> and D<sub>2</sub> in L-ZrO<sub>2</sub>@mSiO<sub>2</sub>.</p><p>Low-energy pathways were investigated computationally using density functional theory (DFT), and several plausible models for hydrogenolysis of <i>n</i>-hexane by the Zr(O)<sub>2</sub>/ZrO<sub>2</sub> species at 300 °C under 0.1 MPa of H<sub>2</sub> are presented here (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig6">6</a>). Although the experimental study focused primarily on polyethylene, the secondary cleavage of the C<sub>18</sub>-centred primary products and hydrogenolysis of hexatriacontane indicate that L-ZrO<sub>2</sub>@mSiO<sub>2</sub> is also a catalyst for small-molecule hydrogenolysis. Hexane and the low-coordinated Zr(O)<sub>2</sub> react through an initial C–H bond activation to form H<sub>13</sub>C<sub>6</sub>-Zr(O)(OH)/ZrO<sub>2</sub> (<b>a1</b> → <b>a2</b>), involving transfer of a hexane H atom to one of the O atoms and the hexyl group to the Zr atom. This step, as well as the heterolytic H<sub>2</sub> cleavage above, is reminiscent of 1,2-addition of a C–H or H–H bond across Zr=NR to give C–Zr–NHR or H–Zr–NHR<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 38" title="Walsh, P. J., Hollander, F. J. & Bergman, R. G. Generation, alkyne cycloaddition, arene carbon–hydrogen activation, nitrogen–hydrogen activation and dative ligand trapping reactions of the first monomeric imidozirconocene (Cp2Zr:NR) complexes. J. Am. Chem. Soc. 110, 8729–8731 (1988)." href="/articles/s41929-023-00910-x#ref-CR38" id="ref-link-section-d10980768e2456">38</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 39" title="Cummins, C. C., Baxter, S. M. & Wolczanski, P. T. Methane and benzene activation via transient (tert-Bu3SiNH)2Zr=NSi-tert-Bu3. J. Am. Chem. Soc. 110, 8731–8733 (1988)." href="/articles/s41929-023-00910-x#ref-CR39" id="ref-link-section-d10980768e2459">39</a></sup>. Hexane metalation by HZr(OH)(O)/ZrO<sub>2</sub> to give H<sub>13</sub>C<sub>6</sub>-Zr(O)(OH)/ZrO<sub>2</sub> with liberation of H<sub>2</sub> (<b>b1</b> → <b>a2</b>), similar to the σ-bond metathesis reaction of (SiO)<sub>3</sub>ZrH and hydrocarbons<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 15" title="Dufaud, V. & Basset, J.-M. Catalytic hydrogenolysis at low temperature and pressure of polyethylene and polypropylene to diesels or lower alkanes by a zirconium hydride supported on silica-alumina: a step toward polyolefin degradation by the microscopic reverse of Ziegler–Natta polymerization. Angew. Chem. Int. Ed. 37, 806–810 (1998)." href="/articles/s41929-023-00910-x#ref-CR15" id="ref-link-section-d10980768e2483">15</a></sup>, is ruled out by its 0.5 eV higher barrier than that of hexane dissociative adsorption on Zr(O)<sub>2</sub>/ZrO<sub>2</sub>.</p><div class="c-article-section__figure js-c-reading-companion-figures-item" data-test="figure" data-container-section="figure" id="figure-6" data-title="Calculated mechanistic model for hydrocarbon hydrogenolysis."><figure><figcaption><b id="Fig6" class="c-article-section__figure-caption" data-test="figure-caption-text">Fig. 6: Calculated mechanistic model for hydrocarbon hydrogenolysis.</b></figcaption><div class="c-article-section__figure-content"><div class="c-article-section__figure-item"><a class="c-article-section__figure-link" data-test="img-link" data-track="click" data-track-label="image" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/6" rel="nofollow"><picture><source type="image/webp" srcset="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig6_HTML.png?as=webp"><img aria-describedby="Fig6" src="//media.springernature.com/lw685/springer-static/image/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_Fig6_HTML.png" alt="figure 6" loading="lazy" width="685" height="585"></picture></a></div><div class="c-article-section__figure-description" data-test="bottom-caption" id="figure-6-desc"><p><b>a</b>, Schematic of the reaction pathways considered for <i>n</i>-hexane hydrogenolysis on the Zr(O)<sub>2</sub>/m-ZrO<sub>2</sub> and H–Zr(O)(OH)/m-ZrO<sub>2</sub> models. <b>b</b>, Corresponding free energy profiles (<i>T</i> = 300 °C; <i>P</i><sub>gas</sub> = 0.1 MPa). All free energies are with reference to the sum of the energies of the Zr(O)<sub>2</sub>/m-ZrO<sub>2</sub> catalyst model and the reactant gas molecules. <b>c</b>, Transition state calculated for C–C bond dissociation.</p></div></div><div class="u-text-right u-hide-print"><a class="c-article__pill-button" data-test="article-link" data-track="click" data-track-label="button" data-track-action="view figure" href="/articles/s41929-023-00910-x/figures/6" data-track-dest="link:Figure6 Full size image" aria-label="Full size image figure 6" rel="nofollow"><span>Full size image</span><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-right-small"></use></svg></a></div></figure></div><p>Kinetically favourable cleavage of the β-C–H bond in H<sub>13</sub>C<sub>6</sub>-Zr(O)(OH)/ZrO<sub>2</sub> produces <i>cis</i>-2-hexene (<b>a2</b> → <b>c1</b>; <i>G</i><sup>act</sup> = 0.94 eV), 1-hexene or <i>trans</i>-2-hexene (via a <0.3 eV higher barrier compared with <i>cis</i>-2-hexene). Alternatively, the 1.26 eV barrier for β-C–C bond cleavage in H<sub>13</sub>C<sub>6</sub>-Zr(O)(OH)/ZrO<sub>2</sub> to give <b>a3</b> is slightly higher. After hydrogenation of the propene product to propane, this pathway is thermodynamically more favourable than the endergonic formation of <i>cis</i>-2-hexene. Our calculations predicted a free energy of 1.8 eV for the C–C bond cleavage transition state over the Zr(O)<sub>2</sub> model, which is the highest-energy state in the free energy profiles of Zr(O)<sub>2</sub> active site models (Fig. <a data-track="click" data-track-label="link" data-track-action="figure anchor" href="/articles/s41929-023-00910-x#Fig6">6</a>). Thus, this process could be rate limiting for <i>n</i>-hexane and possibly also polyethylene hydrogenolysis. In addition, C–H or C–C bond cleavage steps solely based on acidic Zr(OH) have much higher activation barriers (<i>G</i><sup>act</sup> = 2.05 and 2.30 eV, respectively) than 1,2-addition and β-elimination. A bona fide acid catalyst, beta zeolite, under the standard hydrogenolysis condition gave coke and branched products in experiments using polyethylene. The differences between acid- and L-ZrO<sub>2</sub>@mSiO<sub>2</sub>-catalysed deconstructions further support the organozirconia-catalysed computational mechanism.</p><p>Propane is eliminated by a proton transfer from the proximal hydroxy to the propylzirconium species to regenerate the Zr(O)<sub>2</sub> species; the protonolytic propane elimination distinguishes this pathway from the σ-bond metathesis mechanism typically proposed for reactions of H<sub>2</sub> and molecular organozirconium compounds in solution. The activation barrier for an alternative mechanism involving the σ-bond metathesis-type reaction of H<sub>7</sub>C<sub>3</sub>–Zr(O)(OH) and H<sub>2</sub>, as established for catalytic alkene hydrogenation or alkane hydrogenolysis by seemingly related SOMC species (≡SiO)<sub>3</sub>ZrH<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 40" title="Corker, J. et al. Catalytic cleavage of the C–H and C–C bonds of alkanes by surface organometallic chemistry: an EXAFS and IR characterization of a Zr–H catalyst. Science 271, 966–969 (1996)." href="/articles/s41929-023-00910-x#ref-CR40" id="ref-link-section-d10980768e2618">40</a></sup>, is ~0.4 eV higher than protonolytic elimination and appears less likely. In support of this idea, the reaction of grafted ≡Si–O–Zr(CH<sub>2</sub>CMe<sub>3</sub>)<sub>3</sub> and H<sub>2</sub> requires several hours at 150 °C. Although the hydridozirconium species H–Zr(O)OH is neither involved in C–H bond metalation nor formed from H<sub>7</sub>C<sub>3</sub>–Zr(O)(OH) and H<sub>2</sub>, it is nonetheless essential for hydrogenation of propene (<b>a5</b> → <b>a7</b>).</p><p>These reaction steps were confirmed by parahydrogen (pH<sub>2</sub>)-induced polarization (PHIP) NMR spectroscopy, a technique that produces NMR signal enhancements only when the hydrogenation with pH<sub>2</sub> occurs by pairwise addition. The <sup>1</sup>H PHIP NMR spectrum for L-ZrO<sub>2</sub>@mSiO<sub>2</sub>-catalysed propene hydrogenation under ALTADENA (adiabatic longitudinal transport after dissociation engenders net alignment)<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 41" title="Pravica, M. G. & Weitekamp, D. P. Net NMR alignment by adiabatic transport of parahydrogen addition products to high magnetic field. Chem. Phys. Lett. 145, 255–258 (1988)." href="/articles/s41929-023-00910-x#ref-CR41" id="ref-link-section-d10980768e2657">41</a></sup> conditions using 99% pH<sub>2</sub> (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">108</a>) showed net alignment multiplet patterns of the CH<sub>2</sub> and CH<sub>3</sub> peaks with integral ratios close to 1:−1. Thus, the propane product had received both protons from the same pH<sub>2</sub> molecule with retention of spin–spin coupling<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 42" title="Bowers, C. R. & Weitekamp, D. P. Parahydrogen and synthesis allow dramatically enhanced nuclear alignment. J. Am. Chem. Soc. 109, 5541–5542 (1987)." href="/articles/s41929-023-00910-x#ref-CR42" id="ref-link-section-d10980768e2673">42</a></sup>, in accordance with the steps <b>a5</b> → <b>a7</b>. The σ-bond metathesis reaction of H<sub>2</sub> and propylzirconium transfers only a single proton from a pH<sub>2</sub> molecule and cannot produce the NMR signal enhancements in accordance with the above calculations. Moreover, 1,2-addition of the hydrocarbon CH bond (for example, <b>a1</b> → <b>a2</b>) is the reverse reaction of propane elimination, by H transfer from OH to propylzirconium (<b>a6</b> → <b>a7</b>). The principle of microscopic reversibility and the PHIP results together indicate that hydrocarbon metalation on L-ZrO<sub>2</sub>@mSiO<sub>2</sub> is more consistent with 1,2-addition than dehydrogenative metalation by σ-bond metathesis, again in line with the calculations.</p><p>A microkinetic model was used to further examine the <i>n</i>-hexane hydrogenolysis over the Zr(O)<sub>2</sub>/m-ZrO<sub>2</sub> active site, employing a continuous stirred-tank reactor (CSTR; <i>T</i> = 300 °C; <span class="mathjax-tex">$P_{{\rm{H}}_{2}}$</span> = 1 MPa; <i>P</i><sub>hexane</sub> = 0.1 MPa; Table <a data-track="click" data-track-label="link" data-track-action="table anchor" href="/articles/s41929-023-00910-x#Tab1">1</a>). The model revealed that as hexane conversion increases with increased residence time, selectivity for the C–C bond cleavage product, propane, increases to 100% at sufficiently high residence times. These results suggest that the C–C bond cleavage is favoured in the presence of H<sub>2</sub>, which shifts the equilibria towards the propane formation. The microkinetic model also predicted a high steady-state surface coverage of H–Zr(O)OH (<i>θ</i> = 0.63) under H<sub>2</sub> (1 MPa), which further promoted the conversion of propene to propane. Reasonable turnover frequencies, on the order of 10<sup>–4</sup> s<sup>–1</sup>, were observed in the microkinetic model when hexane conversion to propane was between 0.1 and 12.4%.</p><div class="c-article-table" data-test="inline-table" data-container-section="table" id="table-1"><figure><figcaption class="c-article-table__figcaption"><b id="Tab1" data-test="table-caption">Table 1 Conversion, selectivity and turnover frequencies of <i>n</i>-hexane hydrogenolysis predicted by the microkinetic CSTR model for the Zr(O)<sub>2</sub>/m-ZrO<sub>2</sub> active site with respect to the effective residence time<sup>a</sup></b></figcaption><div class="u-text-right u-hide-print"><a class="c-article__pill-button" data-test="table-link" data-track="click" data-track-action="view table" data-track-label="button" rel="nofollow" href="/articles/s41929-023-00910-x/tables/1" aria-label="Full size table 1"><span>Full size table</span><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-right-small"></use></svg></a></div></figure></div><p>The activation barriers of H<sub>2</sub> dissociation and the rate-limiting C–C bond cleavage calculated from the Zr(O)<sub>2</sub>/m-ZrO<sub>2</sub> model were compared with those from the most stable flat surfaces of monoclinic ZrO<sub>2</sub> (–111) and tetragonal ZrO<sub>2</sub> (101) surface sites (Supplementary Fig. <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">107</a>). H<sub>2</sub> activation was found to be thermodynamically less favourable on the flat surfaces compared with the Zr(O)<sub>2</sub>/m-ZrO<sub>2</sub> model. The C–C bond cleavage barriers on the flat surfaces are in the range of 2.1–2.4 eV, in contrast with 1.26 eV for low-coordinated Zr sites, indicating that flat crystal surfaces of ZrO<sub>2</sub> are less active for breaking the C–C bonds of hydrocarbons. Thus, these results are consistent with the experimental observation that ultrasmall amorphous ZrO<sub>2</sub> nanoparticles are more active in polyethylene hydrogenolysis than larger crystalline ZrO<sub>2</sub> nanoparticles dominated by more stable flat surfaces.</p></div></div></section><section data-title="Conclusions"><div class="c-article-section" id="Sec6-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="Sec6">Conclusions</h2><div class="c-article-section__content" id="Sec6-content"><p>Our synthetic, spectroscopic and mechanistic investigations of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> reveal the combined architectural and chemical features that enable Earth-abundant, non-reducible metal oxides (Zr, Si and O) to catalyse the selective hydrogenolysis of hydrocarbon polymers. The synthesis of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> shows, remarkably, that ZrO<sub><i>x</i></sub>(OH)<sub>4–<i>x</i></sub> nanoparticles are stable under the hydrolytic conditions necessary for the growth of mesoporous silica and creation of the catalytic architecture with core-localized nanoparticles. Moreover, the coordinatively unsaturated surface sites needed for catalysis are stabilized by covalently embedding the amorphous zirconium nanoparticles in the walls of mesoporous silica. These sites, modelled as Zr(O)<sub>2</sub> surface species in DFT calculations, mediate C–C bond hydrogenolysis with comparable activity to Pt/C. The quantitative comparison of activity across a series of catalysts is based on H<sub>2</sub> consumption or the relationship between the number of C–C bonds that are cleaved and the change in <i>M</i><sub>n</sub> of the entire hydrocarbon population, as determined from the detailed characterization of gas, liquid and solid compositions. This quantitative comparison reveals that the catalytic enhancement observed with L-ZrO<sub>2</sub>@mSiO<sub>2</sub> is more than simply the combination of small crystalline ZrO<sub>2</sub> with mSiO<sub>2</sub>, as shown by the poorer activity of ZrO<sub>2</sub>–6/mSiO<sub>2</sub>.</p><p>In addition, L-ZrO<sub>2</sub>@mSiO<sub>2</sub> provides advantageous selectivity over the other zirconia-based catalysts investigated in this study. Alignment of long chains in the pores<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 16" title="Tennakoon, A. et al. Catalytic upcycling of high-density polyethylene via a processive mechanism. Nat. Catal. 3, 893–901 (2020)." href="/articles/s41929-023-00910-x#ref-CR16" id="ref-link-section-d10980768e3312">16</a></sup>, non-dissociative adsorption of polymer onto the walls of silica and escape of smaller products through the void space between the two mesoporous silica plates may all contribute to higher selectivity. In fact, both L-ZrO<sub>2</sub>@mSiO<sub>2</sub> and L-Pt@mSiO<sub>2</sub> have sites localized at the ends of mesopores and are both more selective than their non-pore-confined analogues. The mechanisms of zirconia- and platinum-catalysed reactions, however, are distinct. In fact, the energetically favourable heterolytic mechanism for H–H and C–H bond cleavage on Zr(O)<sub>2</sub>/ZrO<sub>2</sub> is different from those proposed for reducible oxides or metal nanoparticles, or even the SOMC zirconium hydride, instead resembling 1,2-addition to zirconium imido compounds. This heterolytic cleavage generates O–H and Zr–H or Zr–CH<sub>2</sub>CH<sub>2</sub>R species, which subsequently engage in protonolytic elimination, insertion and β-alkyl elimination. Thus, the proposed active species is a bifunctional (hydroxy)organozirconium oxide species. Access to such species directly from ZrO<sub>2</sub>, rather than by grafting neopentylzirconium onto silica, allows the catalytic architecture to be constructed under aqueous conditions and enables the catalytic chemistry to be accessed with air-stable precursors. In this sense, hydrogenolysis with L-ZrO<sub>2</sub>@mSiO<sub>2</sub> is a previously unrecognized heterogeneous analogue of the SOMC-catalysed C–C cleavage processes.</p></div></div></section><section data-title="Methods"><div class="c-article-section" id="Sec7-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="Sec7">Methods</h2><div class="c-article-section__content" id="Sec7-content"><h3 class="c-article__sub-heading" id="Sec8">Synthesis of L-ZrO<sub>2</sub>@mSiO<sub>2</sub> </h3><p>L-ZrO<sub>2</sub>@mSiO<sub>2</sub> was prepared via a two-step synthesis method. In the first step, precipitated zirconium oxyhydroxide nanoparticles were deposited onto graphene oxide in an aqueous solution to give ZrO<sub>2–<i>x</i></sub>(OH)<sub>2<i>x</i></sub>/graphene oxide. That material was prepared as follows. Urea (0.150 g) was dissolved in deionized H<sub>2</sub>O (100 ml), graphene oxide (10 mg) was added and the mixture was treated in an ultrasonication bath for 30 min. An aqueous solution of ZrCl<sub>4</sub> (0.024 g in 1.25 ml H<sub>2</sub>O) was added dropwise to the graphene oxide suspension and the mixture was stirred for 3 h at room temperature. The mixture was subsequently stirred and heated at 90 °C for 12 h. The solid ZrO<sub><i>x</i></sub>(OH)<sub>4–2<i>x</i></sub>/graphene oxide product was collected by centrifugation, washed with deionized H<sub>2</sub>O (3 × 50 ml) and then dispersed into H<sub>2</sub>O (10 ml). In the second step, mesoporous silica (mSiO<sub>2</sub>) layers were grown onto ZrO<sub><i>x</i></sub>(OH)<sub>4–2<i>x</i></sub>/graphene oxide following the procedure described in Supplementary Information for the synthesis of mSiO<sub>2</sub> platelets. The final product was characterized and displayed a double-layered platelet structure with ultrasmall ZrO<sub>2</sub> nanoparticles in the narrow core.</p><h3 class="c-article__sub-heading" id="Sec9">Catalytic hydrogenolysis</h3><p>The catalytic hydrogenolysis of polyolefins was performed in a glass-lined high-pressure autoclave reactor (250 ml; Parr Instruments) equipped with a mechanical impeller-style stirrer and a thermocouple that extended into the melted polymer<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 16" title="Tennakoon, A. et al. Catalytic upcycling of high-density polyethylene via a processive mechanism. Nat. Catal. 3, 893–901 (2020)." href="/articles/s41929-023-00910-x#ref-CR16" id="ref-link-section-d10980768e3413">16</a></sup>. Polyethylene (3.0 g; <i>M</i><sub>n</sub> = 20,000; <i>Đ</i> = 4.8) and a catalyst (5.5 mg) were placed into the glass-lined reaction vessel. The reactor was assembled and the system was evacuated under reduced pressure (100 Pa) and then refilled with Ar (3×). H<sub>2</sub> was introduced to the desired pressure (0.482 MPa) at room temperature and the reactor was sealed. The reactor was heated to 300 °C and the gauge pressure was increased to 0.896 MPa for experiments running for 2–20 h. All pressure values are reported as the absolute pressure at the reaction temperature (0.992 MPa = 0.896 MPa on the pressure gauge). At the end of the designated time, the reactor was allowed to cool to room temperature. The volatile products were sampled by connecting the cooled reactor to a gas chromatography sampling loop and analysed using a gas chromatography flame ionized detector (FID) and gas chromatography thermal conductivity detector. The mass yield of gas-phase products was obtained from direct gas chromatography-calibrated quantitative analysis of C<sub>1</sub>–C<sub>9</sub> hydrocarbons separated on an Agilent Technologies 5890 gas chromatograph using an Agilent J&W GS-GasPro (0.32 mm × 15 m) capillary column (gas chromatography FID). H<sub>2</sub> was quantified with respect to a He internal standard using a Supelco Carboxen 1000 (4.6 m × 3.175 mm × 2.1 mm stainless steel) packed column (gas chromatography thermal conductivity detector). Dichloromethane was added to the reactor, which was resealed and heated to 100 °C. The reactor was cooled and the mixture was filtered on a Büchner funnel to separate residual insoluble polymer from the dichloromethane-soluble liquid products. The volatile components were evaporated in a rotary evaporator and the yields of extracted liquid species and solid materials were measured. The soluble materials were analysed by calibrated gas chromatography mass spectrometry using an Agilent Technologies 7890A GC system equipped with a FID or an Agilent Technologies 5975C inert MSD mass spectrometer on an Agilent J&W DB-5ht ((5%-phenyl)-methylpolysiloxane; 0.25 mm × 30 m × 0.1 μm) capillary column (see the section ‘Quantification of liquid products’ for details). The solid portion was dissolved in 1,2,4-trichlorobenzene (TCB) at 150 °C and analysed by high-temperature gel permeation chromatography (HT-GPC).</p><h3 class="c-article__sub-heading" id="Sec10">Analysis of the reaction products</h3><p>The solid polymeric residue was analysed by HT-GPC (Agilent-Polymer Laboratories 220) to determine the molecular weights (<i>M</i><sub>n</sub> and <i>M</i><sub>w</sub>) and molecular weight distributions (<i>Ð</i> = <i>M</i><sub>w</sub>/<i>M</i><sub>n</sub>). The HT-GPC was equipped with refractive index and viscometry detectors. Monodisperse polyethylene standards (PSS Polymer Standards Service) were used for calibration ranging from ~330 Da to ~120 kDa. The column set included three Agilent PLgel MIXED-B columns and one PLgel Mixed-B Guard column. TCB containing 0.01 wt% 3,5-di-<i>tert</i>-butyl-4-hydroxytoluene was used as the eluent at a flow rate of 1.0 ml min<sup>−1</sup> at 160 °C. The lubricant samples were prepared in TCB at a concentration of ~5.0 mg ml<sup>−1</sup> and heated at 150 °C for 24 h before injection.</p><h3 class="c-article__sub-heading" id="Sec11">Quantification of liquid products</h3><p>The composition of the dichloromethane-extracted liquid products, in terms of amounts of each chain length in the samples, was estimated using our previously reported approach<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 16" title="Tennakoon, A. et al. Catalytic upcycling of high-density polyethylene via a processive mechanism. Nat. Catal. 3, 893–901 (2020)." href="/articles/s41929-023-00910-x#ref-CR16" id="ref-link-section-d10980768e3476">16</a></sup>, summarized here briefly for convenience. Gas chromatography mass spectrometry of the ASTM standard was integrated. A plot of the integrated area versus the carbon number allowed determination of the response of all C<sub><i>n</i></sub> values (since the ASTM standard does not include C<sub>13</sub>, C<sub>19</sub>, C<sub>21</sub> and so on) by interpolation. The regions of C<sub>6</sub>–C<sub>20</sub> and C<sub>20</sub>–C<sub>40</sub> are linear, but with inequivalent slopes. Therefore, these two regions were fit separately and used as calibration curves for liquid products.</p><h3 class="c-article__sub-heading" id="Sec12">Estimation of C–C bond cleavage from mass balance</h3><p><i>M</i><sub>n</sub> can be calculated as the total weight of polymer <i>W</i> divided by the total number of chains <i>N</i>. Under reaction, the number of chains grows over time, with each cleavage reaction producing one new chain. The number of chains may then be expressed as</p><div id="Equ1" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$N(t) = N\left( 0 \right) + \mathop {\int}\limits_0^t {r_{{\rm{cut}}}} {\rm{d}}t$$</span></div><div class="c-article-equation__number"> (1) </div></div><p>where <i>r</i><sub>cut</sub> is the rate of cleavage in cuts per unit time. This may be substituted into the expression for <i>M</i><sub>n</sub>:</p><div id="Equ2" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$M_{\rm{n}}\left( t \right) = \frac{W}{{N(t)}} = \frac{{M_{\rm{n}}\left( 0 \right)W}}{{W + M_{\rm{n}}(0){\int}_0^t {r_{{\rm{cut}}}} {\rm{d}}t}}$$</span></div><div class="c-article-equation__number"> (2) </div></div><p>Assuming the cleavage rate is constant and rearranging for <i>r</i><sub>cut</sub>:</p><div id="Equ3" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$r_{{\rm{cut}}} = \frac{W}{t}\left( {\frac{1}{{M_{\rm{n}}(t)}} - \frac{1}{{M_{\rm{n}}\left( 0 \right)}}} \right)$$</span></div><div class="c-article-equation__number"> (3) </div></div><p>For this relationship to be accurate, the <i>M</i><sub>n</sub> used must be that of the entire population. As the polymer in this work was analysed in separate groups depending on the molecular weight, these analyses must be combined to determine the overall <i>M</i><sub>n</sub>. As the number average is the first moment of the distribution, the <i>M</i><sub>n</sub> of the entire population is the weighted average of the groups:</p><div id="Equ4" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$M_{{\rm{n}},{\rm{total}}} = \frac{{{\sum} {W_i} M_{{\rm{n}},i}}}{{{\sum} {W_i} }}$$</span></div><div class="c-article-equation__number"> (4) </div></div><p>where the <i>W</i><sub><i>i</i></sub> is the mass of an analysed group, <i>M</i><sub>n,<i>i</i></sub> is its number-averaged molecular weight and the summations are over all analysed groups. This result is valid for any number of groups and is true even when polymers of the same size may exist in multiple groups. <i>M</i><sub>n,total</sub> may then be used to estimate the C–C bond cleavage rate, per equation (<a data-track="click" data-track-label="link" data-track-action="equation anchor" href="/articles/s41929-023-00910-x#Equ3">3</a>).</p><h3 class="c-article__sub-heading" id="Sec13">DFT calculations</h3><p>DFT calculations related to the reaction network of hexane activation over the ZrO<sub><i>x</i></sub>H<sub><i>y</i></sub> models supported on the (−111) surface of monoclinic ZrO<sub>2</sub> were performed using the periodic plane-wave code Vienna ab initio simulation package (VASP 5.4)<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 43" title="Kresse, G. & Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium. Phys. Rev. B 49, 14251–14269 (1994)." href="/articles/s41929-023-00910-x#ref-CR43" id="ref-link-section-d10980768e4071">43</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 44" title="Kresse, G. & Furthmüller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mater. Sci. 6, 15–50 (1996)." href="/articles/s41929-023-00910-x#ref-CR44" id="ref-link-section-d10980768e4074">44</a></sup>. The ion–electron interaction was described by pseudopotentials constructed within the projector augmented wave framework<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 45" title="Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994)." href="/articles/s41929-023-00910-x#ref-CR45" id="ref-link-section-d10980768e4078">45</a></sup>. The Perdew–Burke–Ernzerhof<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 46" title="Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996)." href="/articles/s41929-023-00910-x#ref-CR46" id="ref-link-section-d10980768e4083">46</a></sup> functional form of the generalized gradient approximation was used to treat electron exchange–correlation effects and Grimme’s DFT-D3<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 47" title="Grimme, S., Antony, J., Ehrlich, S. & Krieg, H. A consistent and accurate ab initio parametrization of density functional dispersion correction (DFT-D) for the 94 elements H–Pu. J. Chem. Phys. 132, 154104 (2010)." href="/articles/s41929-023-00910-x#ref-CR47" id="ref-link-section-d10980768e4087">47</a></sup> method was used to semiempirically describe the van der Waals interactions. To partially account for the self-interaction errors associated with the generalized gradient approximation Perdew–Burke–Ernzerhof functional, we used the DFT+U methodology by setting the <i>U</i>–<i>J</i> value for the 4d states of Zr to 4 eV<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 22" title="Puigdollers, A. R., Tosoni, S. & Pacchioni, G. Turning a nonreducible into a reducible oxide via nanostructuring: opposite behavior of bulk ZrO2 and ZrO2 nanoparticles toward H2 adsorption. J. Phys. Chem. C 120, 15329–15337 (2016)." href="/articles/s41929-023-00910-x#ref-CR22" id="ref-link-section-d10980768e4097">22</a></sup>. For the structure relaxation, we sampled the Brillouin zone by a 2 × 2 × 1 Monkhorst–Pack <i>k</i>-mesh applying a Gaussian smearing approach (<i>σ</i> = 0.05 eV) with a plane-wave kinetic energy cut-off of 500 eV. All of the calculations included dipole and quadrupole corrections for the energies as implemented in VASP using a modified version of the Makov and Payne method<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 48" title="Makov, G. & Payne, M. C. Periodic boundary conditions in ab initio calculations. Phys. Rev. B 51, 4014–4022 (1995)." href="/articles/s41929-023-00910-x#ref-CR48" id="ref-link-section-d10980768e4108">48</a></sup>, and Harris–Foulke-type corrections<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 49" title="Harris, J. Simplified method for calculating the energy of weakly interacting fragments. Phys. Rev. B 31, 1770–1779 (1985)." href="/articles/s41929-023-00910-x#ref-CR49" id="ref-link-section-d10980768e4112">49</a></sup> were applied for the forces. The transition state structures were determined using the climbing image nudged elastic band<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 50" title="Henkelman, G., Uberuaga, B. P. & Jónsson, H. A climbing image nudged elastic band method for finding saddle points and minimum energy paths. J. Chem. Phys. 113, 9901–9904 (2000)." href="/articles/s41929-023-00910-x#ref-CR50" id="ref-link-section-d10980768e4116">50</a></sup> and dimer methods<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 51" title="Heyden, A., Bell, A. T. & Keil, F. J. Efficient methods for finding transition states in chemical reactions: comparison of improved dimer method and partitioned rational function optimization method. J. Chem. Phys. 123, 224101 (2005)." href="/articles/s41929-023-00910-x#ref-CR51" id="ref-link-section-d10980768e4120">51</a></sup>.</p><h3 class="c-article__sub-heading" id="Sec14">Microkinetic CSTR model for hexane hydrogenolysis over the ZrO<sub><i>x</i></sub>H<sub><i>y</i></sub>/m-ZrO<sub>2</sub> model</h3><p>The rate constants for elementary surface reactions and adsorption processes were calculated using classical harmonic transition state theory and collision theory, respectively. A detailed description of the methodology can be found in our recent report<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 52" title="You, K.-E., Ammal, S. C., Lin, Z. & Heyden, A. Understanding selective hydrodeoxygenation of 1,2- and 1,3-propanediols on Cu/Mo2C via multiscale modeling. ACS Catal. 12, 4581–4596 (2022)." href="/articles/s41929-023-00910-x#ref-CR52" id="ref-link-section-d10980768e4143">52</a></sup>. Vibrational frequencies (<i>ν</i><sub><i>i</i></sub>) obtained from DFT calculations were used to calculate the zero-point energy and vibrational partition functions of the intermediate and transition states. Small computed vibrational frequencies (<50 cm<sup>–1</sup>) for surface species were shifted to 50 cm<sup>–1</sup> since the harmonic approximation cannot accurately predict these small frequencies (these frequencies in effect cancel out). The number of active sites per surface area used to calculate adsorption rate constants was 2.5 × 10<sup>19</sup> m<sup>−2</sup>. The entropy term for hexane adsorption was calculated using the empirical formula <i>S</i><sub>ad</sub><sup>0</sup> (<i>T</i>) = 0.70 × <i>S</i><sub>gas</sub><sup>0</sup> (<i>T</i>) − 3.3<i>R</i>, derived by Campbell and Sellers<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 53" title="Campbell, C. T. & Sellers, J. R. V. The entropies of adsorbed molecules. J. Am. Chem. Soc. 134, 18109–18115 (2012)." href="/articles/s41929-023-00910-x#ref-CR53" id="ref-link-section-d10980768e4182">53</a></sup>.</p><p>The CSTR model was constructed under the assumption of an isobaric and isothermal reactor. The species balance for the ideal gas-phase reactants and products was described as:</p><div id="Equ5" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$\frac{{\partial {{{\mathrm{y}}}}_{i,{\rm{gas}}}}}{{\partial \left( {\frac{{{{\it{t}}}}}{\tau }} \right)}} = y_{i,{\rm{gas}},0} - y_{i,{\rm{gas}}}\left( {1 + \tau \times \alpha \mathop {\sum}\limits_i {r_{i,{\rm{gas}}}} } \right) + \tau \times \alpha \times r_{i,{\rm{gas}}}$$</span></div><div class="c-article-equation__number"> (5) </div></div><p>where <i>y</i><sub><i>i,</i>gas,0</sub> and <i>y</i><sub><i>i,</i>gas</sub> correspond to the inlet and outlet mole fractions of gas species <i>i</i>, respectively, <i>t</i> is the time, <i>τ</i> represents a residence time defined as the ratio of the total mole number of gas molecules in the reactor over the total feed flow rate at reactor entrance conditions <i>τ</i> = <i>N</i><sub>tot,0</sub>/<i>F</i><sub>tot,0</sub>, <i>α</i> is the total number of active sites in the reactor over the total mole number of gas molecules in the reactor <i>N</i><sub>cat</sub>/<i>N</i><sub>tot,0</sub> and <i>r</i><sub><i>i</i>,gas</sub> designates a generation rate of gas species <i>i</i> per active site. With the assumption of a constant surface density for the catalyst under various reaction conditions, the value of <i>α</i> was fixed at 1 × 10<sup>–3</sup> and <i>y</i><sub><i>i</i>,gas</sub> was calculated by varying <i>τ</i> at a fixed temperature. The steady-state reactor outlet composition, <i>y</i><sub><i>i</i>,gas</sub>, and overall conversion only depend on the product of <i>α</i> × <i>τ</i> = <i>N</i><sub>cat</sub>/<i>F</i><sub>tot,0</sub>. Thus, meaningful values of <i>α</i> × <i>τ</i> can be obtained from the conversion, and predicting the reactor outlet composition for different <i>τ</i> values is equivalent to predicting the outlet composition for different conversion levels.</p><h3 class="c-article__sub-heading" id="Sec15">PHIP study</h3><p>Hydrogenation of propene over L-ZrO<sub>2</sub>@mSiO<sub>2</sub> was examined by adiabatic longitudinal transport after dissociation engenders net alignment (ALTADENA)<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 41" title="Pravica, M. G. & Weitekamp, D. P. Net NMR alignment by adiabatic transport of parahydrogen addition products to high magnetic field. Chem. Phys. Lett. 145, 255–258 (1988)." href="/articles/s41929-023-00910-x#ref-CR41" id="ref-link-section-d10980768e4499">41</a></sup> NMR experiments using 99% enriched pH<sub>2</sub>. The pH<sub>2</sub> gas was produced by flowing H<sub>2</sub> (Airgas; UHP) through a cryocooled pH<sub>2</sub> converter (Advanced Research Systems) with a catalyst compartment packed with 46 g FeO(OH) (Sigma–Aldrich) at 20 K. The pH<sub>2</sub> and propene (Airgas; UHP) were mixed by combining the outlets of the mass flow controllers (Alicat) for each gas with a total flow rate of 60 sccm and a pH<sub>2</sub>:propene ratio of 5:1. Experiments were performed using 64.9 mg L-ZrO<sub>2</sub>@mSiO<sub>2</sub> packed into a 304 stainless steel reactor tube (McMaster-Carr; 5 cm length; 6.35 mm outer diameter; 3.86 mm internal diameter). The catalyst material was held in place using quartz wool and porous 316 L stainless steel frits (McMaster-Carr; 10 μm pore size) on both ends of the reactor tube. The reactor was mounted in the 4.5 mT fringe field of the 9.4 T Bruker Avance wide bore magnet. The catalyst was pre-treated by flowing an H<sub>2</sub>/N<sub>2</sub> mixture (total flow rate = 50 ml min<sup>−1</sup>; 10% H<sub>2</sub>) through the reactor at 550 °C for 6 h. Propene hydrogenation was carried out by flowing the pH<sub>2</sub>/propene mixture through the catalyst bed at 300 °C at an inlet pressure of 0.294 MPa. The reactor effluent was then transported to the detection coil of a Varian 400 MHz triple-resonance IFC-flow NMR probe at high field (9.4 T) via flow of the gas through approximately 110 cm of 1.59 mm outer diameter PEEK tubing (0.51 mm internal diameter). The <sup>1</sup>H NMR spectrum of the reactor effluent was collected on a 400 MHz Varian VNMRS spectrometer. The continuous-flow hyperpolarized spectrum was acquired by signal averaging of 32 transients using a recycle delay of 1 s and an acquisition time of 0.2 s. The thermally polarized spectrum was acquired after sealing the gas in the NMR probe and signal averaging of 32 transients using a recycle delay of 5 s and an acquisition time of 0.5 s. The propene hydrogenation with normal (n)H<sub>2</sub> (a thermal equilibrium 3:1 mixture of ortho and pH<sub>2</sub>) was also performed under identical conditions. The pure ALTADENA spectrum was obtained by subtracting the continous-flow NMR spectrum acquired using nH<sub>2</sub> from the spectrum acquired with 99% pH<sub>2</sub>. To ensure that the ALTADENA signal was due to hydrogenation over the L-ZrO<sub>2</sub>@mSiO<sub>2</sub> catalyst and not from any other contaminant or metal in the reactor system, control experiments were performed using 99% pH<sub>2</sub> and a reactor tube packed only with an inert filler material (quartz wool). The experimental conditions were otherwise identical. The empty reactor did not yield any detectable conversion, but it did produce a small propane ALTADENA signal with an intensity of ~5% relative to the signal acquired using the L-ZrO<sub>2</sub>@mSiO<sub>2</sub> catalyst at 300 °C. The small background NMR signal appeared to arise from the stainless steel surfaces in the reactor and had been observed in our laboratory previously.</p><h3 class="c-article__sub-heading" id="Sec16">Calculation of conversion</h3><p>The fractional conversion of propene to propane (PA) was calculated from the thermally polarized (TP) spectrum using the following equations:</p><div id="Equ6" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$S_{{\rm{PA}},^{1}{\rm{H}}}^{{\rm{TP}}} = \frac{{S_{{\rm{PA}},{\rm{CH}}_{3}}^{{\rm{TP}}}/6 - X_{{\rm{imp}}} \times S_{{\rm{Propene}},{\rm{CH}}}^{{\rm{TP}}}}}{{1 + X_{{\rm{imp}}}}}$$</span></div><div class="c-article-equation__number"> (6) </div></div><div id="Equ7" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$\chi = \left( {\frac{{S_{{\rm{PA}},^{1}{\rm{H}}}^{{\rm{TP}}}}}{{S_{{\rm{PA}},^{1}{\rm{H}}}^{{\rm{TP}}} + S_{{\rm{Propene}},{\rm{CH}}}^{{\rm{TP}}}}}} \right) \times 100\%$$</span></div><div class="c-article-equation__number"> (7) </div></div><p>where <span class="mathjax-tex">$\chi$</span> is the conversion of propene to propane, <span class="mathjax-tex">$S_{{\rm{PA}},{\rm{CH}}_{3}}^{{\rm{TP}}}$</span> is the measured integral of the PA CH<sub>3</sub> peak in the thermally polarized spectrum, <span class="mathjax-tex">$S_{{\rm{Propene}},{\rm{CH}}}^{{\rm{TP}}}$</span> is the measured integral of the propene CH peak in the thermally polarized spectrum, <span class="mathjax-tex">$S_{{\rm{PA}},^{1}{\rm{H}}}^{{\rm{TP}}}$</span> is the calculated integral per proton of PA after the correction of PA impurity and <span class="mathjax-tex">${{X}}_{{\rm{imp}}}$</span> is the percentage impurity of PA in stock propene (0.26%).</p><h3 class="c-article__sub-heading" id="Sec17">Calculation of signal enhancement</h3><p>The experimental ALTADENA NMR signal enhancement (<i>ε</i>) was evaluated by subtracting the ALTADENA integral of PA CH<sub>3</sub> for the experiment using a stainless steel cartridge with inert fillers from that using L-ZrO<sub>2</sub>@mSiO<sub>2</sub>, then comparing it with the PA CH<sub>3</sub> peak integral of the thermally polarized spectrum:</p><div id="Equ8" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$\varepsilon = \frac{{S_{{\rm{PA}},{\rm{CH}}_{3}}^{{\rm{ZrO}}_{2}} - S_{{\rm{PA}},{\rm{CH}}_{3}}^{{\rm{SS}}}}}{{S_{{\rm{PA}},^{1}{\rm{H}}}^{{\rm{TP}}}}}$$</span></div><div class="c-article-equation__number"> (8) </div></div><p>where <span class="mathjax-tex">$S_{{\rm{PA}},{\rm{CH}}_{3}}^{{\rm{ZrO}}_{2}}$</span> is the integral of the PA CH<sub>3</sub> peak in the ALTADENA spectrum of experiments catalysed by L-ZrO<sub>2</sub>@mSiO<sub>2</sub> and <span class="mathjax-tex">$S_{{\rm{PA}},{\rm{CH}}_{3}}^{{\rm{SS}}}$</span> is the integral of the PA CH<sub>3</sub> peak in the ALTADENA spectrum of experiments catalysed by the stainless steel cartridge with inert fillers.</p><h3 class="c-article__sub-heading" id="Sec18">Calculation of pairwise selectivity</h3><p>The pairwise selectivity (<span class="stix">𝜑</span>) was obtained by dividing the experimental ALTADENA NMR signal enhancement (<i>ε</i>) by the theoretical value (<i>ε</i><sup>theor</sup>, assuming 100% pairwise addition), as in equation (<a data-track="click" data-track-label="link" data-track-action="equation anchor" href="/articles/s41929-023-00910-x#Equ9">9</a>).</p><div id="Equ9" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$\varphi = \frac{\varepsilon }{{\varepsilon ^{{\rm{theor}}}}} \times 100\%$$</span></div><div class="c-article-equation__number"> (9) </div></div><p>For the CH<sub>3</sub> proton of PA, the theoretical ALTADENA signal enhancement was obtained from equation (<a data-track="click" data-track-label="link" data-track-action="equation anchor" href="/articles/s41929-023-00910-x#Equ10">10</a>)<sup><a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 54" title="Zhao, E. W. et al. Silica-encapsulated Pt–Sn intermetallic nanoparticles: a robust catalytic platform for parahydrogen-induced polarization of gases and liquids. Angew. Chem. Int. Ed. 56, 3925–3929 (2017)." href="/articles/s41929-023-00910-x#ref-CR54" id="ref-link-section-d10980768e5443">54</a>,<a data-track="click" data-track-action="reference anchor" data-track-label="link" data-test="citation-ref" aria-label="Reference 55" title="Bowers, C. R. Sensitivity enhancement utilizing parahydrogen. eMagRes https://doi.org/10.1002/9780470034590.emrstm0489 (2007)." href="/articles/s41929-023-00910-x#ref-CR55" id="ref-link-section-d10980768e5446">55</a></sup>.</p><div id="Equ10" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$\varepsilon _{{\rm{ALTADENA}}}^{{\rm{theor}}} = \frac{{2k_{\rm{B}}T(4\chi _{\rm{p}} - 1)}}{{3\hbar \gamma _{\rm{H}}B_0}}$$</span></div><div class="c-article-equation__number"> (10) </div></div><p>where <i>T</i> is the temperature, <i>γ</i><sub>H</sub> is the <sup>1</sup>H gyromagnetic ratio (in rad s<sup>−1</sup>), <i>B</i><sub>0</sub> is the static magnetic field and <i>χ</i><sub>p</sub> is the para-enrichment. When <i>T</i> = 300 K, <i>B</i><sub>0</sub> = 9.4 T and <i>χ</i><sub>p</sub> = 99%, <span class="mathjax-tex">$\varepsilon _{{\rm{ALTADENA}}}^{{\rm{theor}}}$</span> = 31,524.</p><p>Due to the back-conversion of pH<sub>2</sub> to nH<sub>2</sub> by the catalyst during propene hydrogenation, the actual para-enrichment of the H<sub>2</sub> gas within the reactor could be lower than 99%. Indeed, the para-enrichment observed under reaction conditions was only <i>χ</i>′<sub>p</sub> = 58.7% (Table <a data-track="click" data-track-label="link" data-track-action="table anchor" href="/articles/s41929-023-00910-x#Tab2">2</a>), as estimated from equation (<a data-track="click" data-track-label="link" data-track-action="equation anchor" href="/articles/s41929-023-00910-x#Equ11">11</a>):</p><div id="Equ11" class="c-article-equation"><div class="c-article-equation__content"><span class="mathjax-tex">$$\chi _{\rm{p}}^\prime = \left( {1 - \frac{{3S_{{\rm{pH}}_2}}}{{4S_{{\rm{nH}}_2}}}} \right) \times 100{{{\mathrm{\% }}}}$$</span></div><div class="c-article-equation__number"> (11) </div></div><p>where <span class="mathjax-tex">$S_{{\rm{pH}}_2}$</span> and <span class="mathjax-tex">$S_{{\rm{nH}}_2}$</span> represent the integrals of the nH<sub>2</sub> peak in spectra acquired with pH<sub>2</sub> and nH<sub>2</sub>, respectively, in the presence of propene, under reaction conditions. The corrected pairwise selectivity (<i>φ</i>′) was then obtained using equations (<a data-track="click" data-track-label="link" data-track-action="equation anchor" href="/articles/s41929-023-00910-x#Equ9">9</a>)–(<a data-track="click" data-track-label="link" data-track-action="equation anchor" href="/articles/s41929-023-00910-x#Equ11">11</a>).</p><div class="c-article-table" data-test="inline-table" data-container-section="table" id="table-2"><figure><figcaption class="c-article-table__figcaption"><b id="Tab2" data-test="table-caption">Table 2 Hydrogenation of propene over L-ZrO<sub>2</sub>@mSiO<sub>2</sub>—ALTADENA-PHIP NMR results</b></figcaption><div class="u-text-right u-hide-print"><a class="c-article__pill-button" data-test="table-link" data-track="click" data-track-action="view table" data-track-label="button" rel="nofollow" href="/articles/s41929-023-00910-x/tables/2" aria-label="Full size table 2"><span>Full size table</span><svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-chevron-right-small"></use></svg></a></div></figure></div></div></div></section> </div> <div> <section data-title="Data availability"><div class="c-article-section" id="data-availability-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="data-availability">Data availability</h2><div class="c-article-section__content" id="data-availability-content"> <p>The authors declare that the data supporting the findings of this study are available within the paper and its <a data-track="click" data-track-label="link" data-track-action="supplementary material anchor" href="/articles/s41929-023-00910-x#MOESM1">Supplementary Information</a> files or from the corresponding authors upon reasonable request. Atomic coordinates from calculations, NMR spectra and chromatography data that support the findings of this study are available in DataShare at <a href="https://doi.org/10.25380/iastate.21725192">https://doi.org/10.25380/iastate.21725192</a>. <a data-track="click" data-track-label="link" data-track-action="section anchor" href="/articles/s41929-023-00910-x#Sec20">Source data</a> are provided with this paper.</p> </div></div></section><div id="MagazineFulltextArticleBodySuffix"><section aria-labelledby="Bib1" data-title="References"><div class="c-article-section" id="Bib1-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="Bib1">References</h2><div class="c-article-section__content" id="Bib1-content"><div data-container-section="references"><ol class="c-article-references" data-track-component="outbound reference" data-track-context="references section"><li class="c-article-references__item js-c-reading-companion-references-item" data-counter="1."><p class="c-article-references__text" id="ref-CR1">Lwin, S. & Wachs, I. 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The Ames Laboratory is operated by Iowa State University under contract DE-AC-02-07CH11358 (S.C., A.T., K.-E.Y., A.L.P., R.Y., M.S., B.P., K.R.P., S.C.A., F.A.P., A.H., A.D.S. and W.H.) and the Argonne National Laboratory is operated by the UChicago Argonne under contract DE-AC-02-06CH11357 (L.F., R.A.H., M.D., T.L. and B.L.). S.C.A. and A.H. acknowledge partial support from the South Carolina Smart State Center for Strategic Approaches to the Generation of Electricity (SAGE). The pH<sub>2</sub> labelling experiments were supported by National Science Foundation grant CHE-2108306 (T.Y.Z., M.P.L. and C.R.B.) and the National High Magnetic Field Laboratory is supported by the National Science Foundation through NSF/DMR-2128556* and the state of Florida.. This research used resources of the Advanced Photon Source, a DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under contract AC02-06CH11357 (L.F., T.L. and B.L.). Computational resources were provided by XSEDE Resources, located at the San Diego Supercomputer Center, and Texas Advanced Computing Center grant TG-CTS090100 (K.-E.Y., S.C.A. and A.H.), as well as the National Energy Research Scientific Computing Center (NERSC) under contract DE-AC02-05CH11231 (K.-E.Y., S.C.A. and A.H.).</p></div></div></section><section aria-labelledby="author-information" data-title="Author information"><div class="c-article-section" id="author-information-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="author-information">Author information</h2><div class="c-article-section__content" id="author-information-content"><span class="c-article-author-information__subtitle u-visually-hidden" id="author-notes">Author notes</span><ol class="c-article-author-information__list"><li class="c-article-author-information__item" id="na1"><p>These authors contributed equally: Shaojiang Chen, Akalanka Tennakoon, Kyung-Eun You.</p></li></ol><h3 class="c-article__sub-heading" id="affiliations">Authors and Affiliations</h3><ol class="c-article-author-affiliation__list"><li id="Aff1"><p class="c-article-author-affiliation__address">US Department of Energy, Ames National Laboratory, Iowa State University, Ames, IA, USA</p><p class="c-article-author-affiliation__authors-list">Shaojiang Chen, Akalanka Tennakoon, Alexander L. Paterson, Xun Wu, Mukunth Saravanan, Yi-Yu Wang, Long Qi, Frédéric A. Perras, Aaron D. Sadow & Wenyu Huang</p></li><li id="Aff2"><p class="c-article-author-affiliation__address">Department of Chemistry, Iowa State University, Ames, IA, USA</p><p class="c-article-author-affiliation__authors-list">Akalanka Tennakoon, Xun Wu, Yi-Yu Wang, Aaron D. Sadow & Wenyu Huang</p></li><li id="Aff3"><p class="c-article-author-affiliation__address">Department of Chemical Engineering, University of South Carolina, Columbia, SC, USA</p><p class="c-article-author-affiliation__authors-list">Kyung-Eun You, Salai C. Ammal & Andreas Heyden</p></li><li id="Aff4"><p class="c-article-author-affiliation__address">Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA</p><p class="c-article-author-affiliation__authors-list">Ryan Yappert & Baron Peters</p></li><li id="Aff5"><p class="c-article-author-affiliation__address">Center for Catalysis and Surface Science, Northwestern University, Evanston, IL, USA</p><p class="c-article-author-affiliation__authors-list">Selim Alayoglu</p></li><li id="Aff6"><p class="c-article-author-affiliation__address">Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, IL, USA</p><p class="c-article-author-affiliation__authors-list">Lingzhe Fang & Tao Li</p></li><li id="Aff7"><p class="c-article-author-affiliation__address">Department of Chemistry, University of Florida, Gainesville, FL, USA</p><p class="c-article-author-affiliation__authors-list">Tommy Yunpu Zhao, Michelle P. Lapak & Clifford R. Bowers</p></li><li id="Aff8"><p class="c-article-author-affiliation__address">Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA</p><p class="c-article-author-affiliation__authors-list">Ryan A. Hackler & Massimiliano Delferro</p></li><li id="Aff9"><p class="c-article-author-affiliation__address">Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA</p><p class="c-article-author-affiliation__authors-list">Massimiliano Delferro</p></li><li id="Aff10"><p class="c-article-author-affiliation__address">X-ray Science Division, Argonne National Laboratory, Lemont, IL, USA</p><p class="c-article-author-affiliation__authors-list">Tao Li & Byeongdu Lee</p></li><li id="Aff11"><p class="c-article-author-affiliation__address">Department of Chemistry, Northwestern University, Evanston, IL, USA</p><p class="c-article-author-affiliation__authors-list">Kenneth R. 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Bowers</p></li></ol><div class="u-js-hide u-hide-print" data-test="author-info"><span class="c-article__sub-heading">Authors</span><ol class="c-article-authors-search u-list-reset"><li id="auth-Shaojiang-Chen-Aff1"><span class="c-article-authors-search__title u-h3 js-search-name">Shaojiang Chen</span><div class="c-article-authors-search__list"><div class="c-article-authors-search__item c-article-authors-search__list-item--left"><a href="/search?author=Shaojiang%20Chen" class="c-article-button" data-track="click" data-track-action="author link - publication" data-track-label="link" rel="nofollow">View author publications</a></div><div class="c-article-authors-search__item c-article-authors-search__list-item--right"><p class="search-in-title-js c-article-authors-search__text">You can also search for this author in <span class="c-article-identifiers"><a class="c-article-identifiers__item" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=search&term=Shaojiang%20Chen" data-track="click" data-track-action="author link - pubmed" data-track-label="link" rel="nofollow">PubMed</a><span class="u-hide"> </span><a class="c-article-identifiers__item" href="http://scholar.google.co.uk/scholar?as_q=&num=10&btnG=Search+Scholar&as_epq=&as_oq=&as_eq=&as_occt=any&as_sauthors=%22Shaojiang%20Chen%22&as_publication=&as_ylo=&as_yhi=&as_allsubj=all&hl=en" data-track="click" data-track-action="author link - scholar" data-track-label="link" rel="nofollow">Google Scholar</a></span></p></div></div></li><li id="auth-Akalanka-Tennakoon-Aff1-Aff2"><span class="c-article-authors-search__title u-h3 js-search-name">Akalanka Tennakoon</span><div class="c-article-authors-search__list"><div class="c-article-authors-search__item c-article-authors-search__list-item--left"><a href="/search?author=Akalanka%20Tennakoon" class="c-article-button" data-track="click" data-track-action="author link - publication" data-track-label="link" rel="nofollow">View author publications</a></div><div class="c-article-authors-search__item c-article-authors-search__list-item--right"><p class="search-in-title-js c-article-authors-search__text">You can also search for this author in <span class="c-article-identifiers"><a class="c-article-identifiers__item" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=search&term=Akalanka%20Tennakoon" data-track="click" data-track-action="author link - pubmed" data-track-label="link" rel="nofollow">PubMed</a><span class="u-hide"> </span><a class="c-article-identifiers__item" href="http://scholar.google.co.uk/scholar?as_q=&num=10&btnG=Search+Scholar&as_epq=&as_oq=&as_eq=&as_occt=any&as_sauthors=%22Akalanka%20Tennakoon%22&as_publication=&as_ylo=&as_yhi=&as_allsubj=all&hl=en" data-track="click" data-track-action="author link - scholar" data-track-label="link" rel="nofollow">Google Scholar</a></span></p></div></div></li><li id="auth-Kyung_Eun-You-Aff3"><span class="c-article-authors-search__title u-h3 js-search-name">Kyung-Eun You</span><div class="c-article-authors-search__list"><div class="c-article-authors-search__item c-article-authors-search__list-item--left"><a href="/search?author=Kyung-Eun%20You" class="c-article-button" data-track="click" data-track-action="author link - publication" data-track-label="link" rel="nofollow">View author publications</a></div><div class="c-article-authors-search__item c-article-authors-search__list-item--right"><p class="search-in-title-js c-article-authors-search__text">You can also search for this author in <span class="c-article-identifiers"><a class="c-article-identifiers__item" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=search&term=Kyung-Eun%20You" data-track="click" data-track-action="author link - pubmed" data-track-label="link" rel="nofollow">PubMed</a><span class="u-hide"> </span><a class="c-article-identifiers__item" href="http://scholar.google.co.uk/scholar?as_q=&num=10&btnG=Search+Scholar&as_epq=&as_oq=&as_eq=&as_occt=any&as_sauthors=%22Kyung-Eun%20You%22&as_publication=&as_ylo=&as_yhi=&as_allsubj=all&hl=en" data-track="click" data-track-action="author link - scholar" data-track-label="link" rel="nofollow">Google Scholar</a></span></p></div></div></li><li id="auth-Alexander_L_-Paterson-Aff1"><span class="c-article-authors-search__title u-h3 js-search-name">Alexander L. 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The catalytic experiments were performed by A.T. and M.S guided by A.D.S. The analysis of liquid products was performed by A.T., M.S., Y.-Y.W., X.W. and L.Q., guided by A.D.S. and W.H. GPC was performed by R.A.H. under the supervision of M.D. Theoretical calculations were performed by K.-E.Y. and S.C.A., directed by A.H. The numbers of C–C bond cleavage steps were calculated by R.Y. using the model created by B.P. Characterization by solid-state nuclear magnetic resonance was conducted by A.L.P. under the direction of F.A.P. Characterization by X-ray absorption spectroscopy was conducted by L.F., T.L. and B.L. Characterization by ICP-MS was conducted by S.C. and X.W. The DRIFT experiments were performed by S.A. and K.R.P. The PHIP experiments were performed by T.Y.Z., M.P.L, and C.R.B. The manuscript was composed by S.C., A.T., K.-E.Y., A.H., W.H., and A.D.S. with contributions from all other co-authors.</p><h3 class="c-article__sub-heading" id="corresponding-author">Corresponding authors</h3><p id="corresponding-author-list">Correspondence to <a id="corresp-c1" href="mailto:heyden@cec.sc.edu">Andreas Heyden</a>, <a id="corresp-c2" href="mailto:sadow@iastate.edu">Aaron D. Sadow</a> or <a id="corresp-c3" href="mailto:whuang@iastate.edu">Wenyu Huang</a>.</p></div></div></section><section data-title="Ethics declarations"><div class="c-article-section" id="ethics-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="ethics">Ethics declarations</h2><div class="c-article-section__content" id="ethics-content"> <h3 class="c-article__sub-heading" id="FPar2">Competing interests</h3> <p>The authors declare no competing interests.</p> </div></div></section><section data-title="Peer review"><div class="c-article-section" id="peer-review-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="peer-review">Peer review</h2><div class="c-article-section__content" id="peer-review-content"> <h3 class="c-article__sub-heading" id="FPar1">Peer review information</h3> <p><i>Nature Catalysis</i> thanks Bert Weckhuysen, Kinga Gora-Marek and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.</p> </div></div></section><section data-title="Additional information"><div class="c-article-section" id="additional-information-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="additional-information">Additional information</h2><div class="c-article-section__content" id="additional-information-content"><p><b>Publisher’s note</b> Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.</p></div></div></section><section data-title="Supplementary information"><div class="c-article-section" id="Sec19-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="Sec19">Supplementary information</h2><div class="c-article-section__content" id="Sec19-content"><div data-test="supplementary-info"><div id="figshareContainer" class="c-article-figshare-container" data-test="figshare-container"></div><div class="c-article-supplementary__item" data-test="supp-item" id="MOESM1"><h3 class="c-article-supplementary__title u-h3"><a class="print-link" data-track="click" data-track-action="view supplementary info" data-test="supp-info-link" data-track-label="supplementary information" href="https://static-content.springer.com/esm/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_MOESM1_ESM.pdf" data-supp-info-image="">Supplementary Information</a></h3><div class="c-article-supplementary__description" data-component="thumbnail-container"><p>Supplementary methods, Figs. 1–108, Tables 1–10 and references 1–8.</p></div></div></div></div></div></section><section data-title="Source data"><div class="c-article-section" id="Sec20-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="Sec20">Source data</h2><div class="c-article-section__content" id="Sec20-content"><div data-test="supplementary-info"><div class="c-article-supplementary__item" data-test="supp-item" id="MOESM2"><h3 class="c-article-supplementary__title u-h3"><a class="print-link" data-track="click" data-track-action="view supplementary info" data-test="supp-info-link" data-track-label="source data fig. 4" href="https://static-content.springer.com/esm/art%3A10.1038%2Fs41929-023-00910-x/MediaObjects/41929_2023_910_MOESM2_ESM.xlsx" data-supp-info-image="">Source Data Fig. 4</a></h3><div class="c-article-supplementary__description" data-component="thumbnail-container"><p>Statistical source data for catalysis product.</p></div></div></div></div></div></section><section data-title="Rights and permissions"><div class="c-article-section" id="rightslink-section"><h2 class="c-article-section__title js-section-title js-c-reading-companion-sections-item" id="rightslink">Rights and permissions</h2><div class="c-article-section__content" id="rightslink-content"> <p><b>Open Access</b> This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. 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id="citeas">Cite this article</h3><p class="c-bibliographic-information__citation">Chen, S., Tennakoon, A., You, KE. <i>et al.</i> Ultrasmall amorphous zirconia nanoparticles catalyse polyolefin hydrogenolysis. <i>Nat Catal</i> <b>6</b>, 161–173 (2023). https://doi.org/10.1038/s41929-023-00910-x</p><p class="c-bibliographic-information__download-citation u-hide-print"><a data-test="citation-link" data-track="click" data-track-action="download article citation" data-track-label="link" data-track-external="" rel="nofollow" href="https://citation-needed.springer.com/v2/references/10.1038/s41929-023-00910-x?format=refman&flavour=citation">Download citation<svg width="16" height="16" focusable="false" role="img" aria-hidden="true" class="u-icon"><use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="#icon-eds-i-download-medium"></use></svg></a></p><ul class="c-bibliographic-information__list" data-test="publication-history"><li 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