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class="vector-toc-list"> </ul> </li> <li id="toc-Galvanic_cell" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Galvanic_cell"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Galvanic cell</span> </div> </a> <ul id="toc-Galvanic_cell-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Electroplating_metal_cathode_(electrolysis)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Electroplating_metal_cathode_(electrolysis)"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3</span> <span>Electroplating metal cathode (electrolysis)</span> </div> </a> <ul id="toc-Electroplating_metal_cathode_(electrolysis)-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-In_electronics" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#In_electronics"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>In electronics</span> </div> </a> <button aria-controls="toc-In_electronics-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle In electronics subsection</span> </button> <ul id="toc-In_electronics-sublist" class="vector-toc-list"> <li id="toc-Vacuum_tubes" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Vacuum_tubes"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Vacuum tubes</span> </div> </a> <ul id="toc-Vacuum_tubes-sublist" class="vector-toc-list"> <li id="toc-Hot_cathode" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Hot_cathode"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1.1</span> <span>Hot cathode</span> </div> </a> <ul id="toc-Hot_cathode-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Cold_cathode" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Cold_cathode"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1.2</span> <span>Cold cathode</span> </div> </a> <ul id="toc-Cold_cathode-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Diodes" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Diodes"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Diodes</span> </div> </a> <ul id="toc-Diodes-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Cathode</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 66 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-66" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">66 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%85%D9%87%D8%A8%D8%B7_(%D9%83%D9%8A%D9%85%D9%8A%D8%A7%D8%A1)" title="مهبط (كيمياء) – Arabic" lang="ar" hreflang="ar" data-title="مهبط (كيمياء)" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/C%C3%A1todu" title="Cátodu – Asturian" lang="ast" hreflang="ast" data-title="Cátodu" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Katod" title="Katod – Azerbaijani" lang="az" hreflang="az" data-title="Katod" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-azb mw-list-item"><a href="https://azb.wikipedia.org/wiki/%DA%A9%D8%A7%D8%AA%D9%88%D8%AF" title="کاتود – South Azerbaijani" lang="azb" hreflang="azb" data-title="کاتود" data-language-autonym="تۆرکجه" data-language-local-name="South Azerbaijani" class="interlanguage-link-target"><span>تۆرکجه</span></a></li><li class="interlanguage-link interwiki-zh-min-nan mw-list-item"><a href="https://zh-min-nan.wikipedia.org/wiki/Im-ke%CC%8Dk" title="Im-ke̍k – Minnan" lang="nan" hreflang="nan" data-title="Im-ke̍k" data-language-autonym="閩南語 / Bân-lâm-gú" data-language-local-name="Minnan" class="interlanguage-link-target"><span>閩南語 / Bân-lâm-gú</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4" title="Катод – Belarusian" lang="be" hreflang="be" data-title="Катод" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4" title="Катод – Bulgarian" lang="bg" hreflang="bg" data-title="Катод" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Katoda" title="Katoda – Bosnian" lang="bs" hreflang="bs" data-title="Katoda" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/C%C3%A0tode" title="Càtode – Catalan" lang="ca" hreflang="ca" data-title="Càtode" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4" title="Катод – Chuvash" lang="cv" hreflang="cv" data-title="Катод" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Katoda" title="Katoda – Czech" lang="cs" hreflang="cs" data-title="Katoda" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Cathod" title="Cathod – Welsh" lang="cy" hreflang="cy" data-title="Cathod" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Katode" title="Katode – Danish" lang="da" hreflang="da" data-title="Katode" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Kathode" title="Kathode – German" lang="de" hreflang="de" data-title="Kathode" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Katood" title="Katood – Estonian" lang="et" hreflang="et" data-title="Katood" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/C%C3%A1todo" title="Cátodo – Spanish" lang="es" hreflang="es" data-title="Cátodo" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Katodo" title="Katodo – Esperanto" lang="eo" hreflang="eo" data-title="Katodo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Katodo" title="Katodo – Basque" lang="eu" hreflang="eu" data-title="Katodo" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%DA%A9%D8%A7%D8%AA%D8%AF" title="کاتد – Persian" lang="fa" hreflang="fa" data-title="کاتد" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Cathode" title="Cathode – French" lang="fr" hreflang="fr" data-title="Cathode" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Cat%C3%B3id" title="Catóid – Irish" lang="ga" hreflang="ga" data-title="Catóid" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/C%C3%A1todo" title="Cátodo – Galician" lang="gl" hreflang="gl" data-title="Cátodo" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%BA%90%EC%86%8C%EB%93%9C" title="캐소드 – Korean" lang="ko" hreflang="ko" data-title="캐소드" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D4%BF%D5%A1%D5%BF%D5%B8%D5%A4_(%D5%A1%D5%B5%D5%AC_%D5%AF%D5%AB%D6%80%D5%A1%D5%BC%D5%B8%D6%82%D5%B4%D5%B6%D5%A5%D6%80)" title="Կատոդ (այլ կիրառումներ) – Armenian" lang="hy" hreflang="hy" data-title="Կատոդ (այլ կիրառումներ)" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%95%E0%A5%88%E0%A4%A5%E0%A5%8B%E0%A4%A1" title="कैथोड – Hindi" lang="hi" hreflang="hi" data-title="कैथोड" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Katoda" title="Katoda – Croatian" lang="hr" hreflang="hr" data-title="Katoda" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-io mw-list-item"><a href="https://io.wikipedia.org/wiki/Katodo" title="Katodo – Ido" lang="io" hreflang="io" data-title="Katodo" data-language-autonym="Ido" data-language-local-name="Ido" class="interlanguage-link-target"><span>Ido</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Katode" title="Katode – Indonesian" lang="id" hreflang="id" data-title="Katode" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Bakskaut" title="Bakskaut – Icelandic" lang="is" hreflang="is" data-title="Bakskaut" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Catodo" title="Catodo – Italian" lang="it" hreflang="it" data-title="Catodo" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4" title="Катод – Kazakh" lang="kk" hreflang="kk" data-title="Катод" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/Kat%C3%B2d" title="Katòd – Haitian Creole" lang="ht" hreflang="ht" data-title="Katòd" data-language-autonym="Kreyòl ayisyen" data-language-local-name="Haitian Creole" class="interlanguage-link-target"><span>Kreyòl ayisyen</span></a></li><li class="interlanguage-link interwiki-ky mw-list-item"><a href="https://ky.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4" title="Катод – Kyrgyz" lang="ky" hreflang="ky" data-title="Катод" data-language-autonym="Кыргызча" data-language-local-name="Kyrgyz" class="interlanguage-link-target"><span>Кыргызча</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Katods" title="Katods – Latvian" lang="lv" hreflang="lv" data-title="Katods" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Katodas" title="Katodas – Lithuanian" lang="lt" hreflang="lt" data-title="Katodas" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Kat%C3%B3d" title="Katód – Hungarian" lang="hu" hreflang="hu" data-title="Katód" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4%D0%B0" title="Катода – Macedonian" lang="mk" hreflang="mk" data-title="Катода" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Kathode" title="Kathode – Dutch" lang="nl" hreflang="nl" data-title="Kathode" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%82%AB%E3%82%BD%E3%83%BC%E3%83%89" title="カソード – Japanese" lang="ja" hreflang="ja" data-title="カソード" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Katode" title="Katode – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Katode" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nov mw-list-item"><a href="https://nov.wikipedia.org/wiki/Katode" title="Katode – Novial" lang="nov" hreflang="nov" data-title="Katode" data-language-autonym="Novial" data-language-local-name="Novial" class="interlanguage-link-target"><span>Novial</span></a></li><li class="interlanguage-link interwiki-om mw-list-item"><a href="https://om.wikipedia.org/wiki/Kaatodii" title="Kaatodii – Oromo" lang="om" hreflang="om" data-title="Kaatodii" data-language-autonym="Oromoo" data-language-local-name="Oromo" class="interlanguage-link-target"><span>Oromoo</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Katod" title="Katod – Uzbek" lang="uz" hreflang="uz" data-title="Katod" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Katoda" title="Katoda – Polish" lang="pl" hreflang="pl" data-title="Katoda" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/C%C3%A1todo" title="Cátodo – Portuguese" lang="pt" hreflang="pt" data-title="Cátodo" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Catod" title="Catod – Romanian" lang="ro" hreflang="ro" data-title="Catod" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-rue mw-list-item"><a href="https://rue.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4%D0%B0" title="Катода – Rusyn" lang="rue" hreflang="rue" data-title="Катода" data-language-autonym="Русиньскый" data-language-local-name="Rusyn" class="interlanguage-link-target"><span>Русиньскый</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4" title="Катод – Russian" lang="ru" hreflang="ru" data-title="Катод" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-si mw-list-item"><a href="https://si.wikipedia.org/wiki/%E0%B6%9A%E0%B7%90%E0%B6%AD%E0%B7%9D%E0%B6%A9%E0%B6%BA" title="කැතෝඩය – Sinhala" lang="si" hreflang="si" data-title="කැතෝඩය" data-language-autonym="සිංහල" data-language-local-name="Sinhala" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Cathode" title="Cathode – Simple English" lang="en-simple" hreflang="en-simple" data-title="Cathode" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Kat%C3%B3da" title="Katóda – Slovak" lang="sk" hreflang="sk" data-title="Katóda" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Katoda" title="Katoda – Slovenian" lang="sl" hreflang="sl" data-title="Katoda" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%DA%A9%D8%A7%D8%AA%DB%86%D8%AF" title="کاتۆد – Central Kurdish" lang="ckb" hreflang="ckb" data-title="کاتۆد" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9A%D0%B0%D1%82%D0%BE%D0%B4%D0%B0" title="Катода – Serbian" lang="sr" hreflang="sr" data-title="Катода" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Katoda" title="Katoda – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Katoda" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Katodi" title="Katodi – Finnish" lang="fi" hreflang="fi" data-title="Katodi" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li 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title="Cathode – Vietnamese" lang="vi" hreflang="vi" data-title="Cathode" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E9%98%B4%E6%9E%81" title="阴极 – Wu" lang="wuu" hreflang="wuu" data-title="阴极" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E9%99%B0%E6%A5%B5" title="陰極 – Cantonese" lang="yue" hreflang="yue" data-title="陰極" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E9%99%B0%E6%A5%B5" title="陰極 – Chinese" lang="zh" hreflang="zh" data-title="陰極" 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<div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Electrode where reduction takes place</div> <p class="mw-empty-elt"> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Copper_cathode_2.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Copper_cathode_2.svg/220px-Copper_cathode_2.svg.png" decoding="async" width="220" height="282" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Copper_cathode_2.svg/330px-Copper_cathode_2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/90/Copper_cathode_2.svg/440px-Copper_cathode_2.svg.png 2x" data-file-width="468" data-file-height="600" /></a><figcaption>Diagram of a <a href="/wiki/Copper" title="Copper">copper</a> cathode in a <a href="/wiki/Galvanic_cell" title="Galvanic cell">galvanic cell</a> (e.g., a battery). Positively charged cations move towards the cathode allowing a positive current <i>i</i> to flow out of the cathode.</figcaption></figure> <p>A <b>cathode</b> is the <a href="/wiki/Electrode" title="Electrode">electrode</a> from which a <a href="/wiki/Conventional_current" class="mw-redirect" title="Conventional current">conventional current</a> leaves a polarized electrical device such as a <a href="/wiki/Lead-acid_battery" class="mw-redirect" title="Lead-acid battery">lead-acid battery</a>. This definition can be recalled by using the <a href="/wiki/Mnemonic" title="Mnemonic">mnemonic</a> <i>CCD</i> for <i>Cathode Current Departs</i>. A conventional current describes the direction in which positive charges move. Electrons have a negative electrical charge, so the movement of electrons is opposite to that of the <a href="/wiki/Conventional_current" class="mw-redirect" title="Conventional current">conventional current</a> flow. Consequently, the mnemonic <i>cathode current departs</i> also means that electrons flow <i>into</i> the device's cathode from the external circuit. For example, the end of a household battery marked with a + (plus) is the cathode. </p><p>The electrode through which conventional current flows the other way, into the device, is termed an <a href="/wiki/Anode" title="Anode">anode</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Charge_flow">Charge flow</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=1" title="Edit section: Charge flow"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Conventional current flows from cathode to anode outside the cell or device (with electrons moving in the opposite direction), regardless of the cell or device type and operating mode. </p><p>Cathode <a href="/wiki/Electrical_polarity" class="mw-redirect" title="Electrical polarity">polarity</a> with respect to the <a href="/wiki/Anode" title="Anode">anode</a> can be positive or negative depending on how the device is being operated. Inside a device or a cell, positively charged <a href="/wiki/Ion" title="Ion">cations</a> always move towards the cathode and negatively charged <a href="/wiki/Ion" title="Ion">anions</a> move towards the anode, although cathode polarity depends on the device type, and can even vary according to the operating mode. Whether the cathode is negatively polarized (such as recharging a battery) or positively polarized (such as a battery in use), the cathode will draw electrons into it from outside, as well as attract positively charged <a href="/wiki/Ion" title="Ion">cations</a> from inside. </p><p>A battery or <a href="/wiki/Galvanic_cell" title="Galvanic cell">galvanic cell</a> in use has a cathode that is the positive terminal since that is where conventional current flows out of the device. This outward current is carried internally by positive ions moving from the <a href="/wiki/Electrolyte" title="Electrolyte">electrolyte</a> to the positive cathode (chemical energy is responsible for this "uphill" motion). It is continued externally by electrons moving into the battery which constitutes positive current flowing outwards. For example, the <a href="/wiki/Daniell_cell" title="Daniell cell">Daniell galvanic cell</a>'s copper electrode is the positive terminal and the cathode. </p><p>A battery that is recharging or an <a href="/wiki/Electrolytic_cell" title="Electrolytic cell">electrolytic cell</a> performing electrolysis has its cathode as the negative terminal, from which current exits the device and returns to the external generator as charge enters the battery/ cell. For example, reversing the current direction in a <a href="/wiki/Daniell_cell" title="Daniell cell">Daniell galvanic cell</a> converts it into an electrolytic cell<sup id="cite_ref-Reversed_Daniell_Cell_1-0" class="reference"><a href="#cite_note-Reversed_Daniell_Cell-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> where the copper electrode is the positive terminal and also the <a href="/wiki/Anode" title="Anode">anode</a>. </p><p>In a <a href="/wiki/Diode" title="Diode">diode</a>, the cathode is the negative terminal at the pointed end of the arrow symbol, where current flows out of the device. Note: electrode naming for diodes is always based on the direction of the forward current (that of the arrow, in which the current flows "most easily"), even for types such as <a href="/wiki/Zener_diode" title="Zener diode">Zener diodes</a> or <a href="/wiki/Solar_cell" title="Solar cell">solar cells</a> where the current of interest is the reverse current. In <a href="/wiki/Vacuum_tube" title="Vacuum tube">vacuum tubes</a> (including <a href="/wiki/Cathode-ray_tube" title="Cathode-ray tube">cathode-ray tubes</a>) it is the negative terminal where electrons enter the device from the external circuit and proceed into the tube's near-vacuum, constituting a positive current flowing out of the device. </p> <div class="mw-heading mw-heading2"><h2 id="Etymology">Etymology</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=2" title="Edit section: Etymology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The word was coined in 1834 from the <a href="/wiki/Greek_language" title="Greek language">Greek</a> κάθοδος (<i>kathodos</i>), 'descent' or 'way down', by <a href="/wiki/William_Whewell" title="William Whewell">William Whewell</a>, who had been consulted<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> by <a href="/wiki/Michael_Faraday" title="Michael Faraday">Michael Faraday</a> over some new names needed to complete a paper on the recently discovered process of electrolysis. In that paper Faraday explained that when an electrolytic cell is oriented so that electric current traverses the "decomposing body" (electrolyte) in a direction "from East to West, or, which will strengthen this help to the memory, that in which the sun appears to move", the cathode is where the current leaves the electrolyte, on the West side: "<i>kata</i> downwards, <i>`odos</i> a way; the way which the sun sets".<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>The use of 'West' to mean the 'out' direction (actually 'out' → 'West' → 'sunset' → 'down', i.e. 'out of view') may appear unnecessarily contrived. Previously, as related in the first reference cited above, Faraday had used the more straightforward term "exode" (the doorway where the current exits). His motivation for changing it to something meaning 'the West electrode' (other candidates had been "westode", "occiode" and "dysiode") was to make it immune to a possible later change in the direction convention for <a href="/wiki/Electric_current" title="Electric current">current</a>, whose exact nature was not known at the time. The reference he used to this effect was the <a href="/wiki/Earth%27s_magnetic_field" title="Earth's magnetic field">Earth's magnetic field</a> direction, which at that time was believed to be invariant. He fundamentally defined his arbitrary orientation for the cell as being that in which the internal current would run parallel to and in the same direction as a hypothetical <a href="/wiki/Solenoid" title="Solenoid">magnetizing current loop</a> around the local line of latitude which would induce a magnetic <a href="/wiki/Dipole" title="Dipole">dipole</a> field oriented like the Earth's. This made the internal current East to West as previously mentioned, but in the event of a later convention change it would have become West to East, so that the West electrode would not have been the 'way out' any more. Therefore, "exode" would have become inappropriate, whereas "cathode" meaning 'West electrode' would have remained correct with respect to the unchanged direction of the actual phenomenon underlying the current, then unknown but, he thought, unambiguously defined by the magnetic reference. In retrospect the name change was unfortunate, not only because the Greek roots alone do not reveal the cathode's function any more, but more importantly because, as we now know, the Earth's magnetic field direction on which the "cathode" term is based is subject to <a href="/wiki/Geomagnetic_reversal" title="Geomagnetic reversal">reversals</a> whereas the <a href="/wiki/Electric_current" title="Electric current">current</a> direction convention on which the "exode" term was based has no reason to change in the future. </p><p>Since the later discovery of the <a href="/wiki/Electron" title="Electron">electron</a>, an easier to remember, and more durably technically correct (although historically false), etymology has been suggested: cathode, from the Greek <i>kathodos</i>, 'way down', 'the way (down) into the cell (or other device) for electrons'. </p> <div class="mw-heading mw-heading2"><h2 id="In_chemistry">In chemistry</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=3" title="Edit section: In chemistry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In <a href="/wiki/Chemistry" title="Chemistry">chemistry</a>, a <b>cathode</b> is the <a href="/wiki/Electrode" title="Electrode">electrode</a> of an <a href="/wiki/Electrochemical_cell" title="Electrochemical cell">electrochemical cell</a> at which <a href="/wiki/Reduction_(chemistry)" class="mw-redirect" title="Reduction (chemistry)">reduction</a> occurs. The cathode can be negative like when the cell is electrolytic (where electrical energy provided to the cell is being used for decomposing chemical compounds); or positive as when the cell is galvanic (where chemical reactions are used for generating electrical energy). The cathode supplies electrons to the positively charged cations which flow to it from the electrolyte (even if the cell is galvanic, i.e., when the cathode is positive and therefore would be expected to repel the positively charged cations; this is due to <a href="/wiki/Electrode_potential" title="Electrode potential">electrode potential</a> relative to the electrolyte solution being different for the anode and cathode metal/electrolyte systems in a <a href="/wiki/Galvanic_cell" title="Galvanic cell">galvanic cell</a>). </p><p>The <b>cathodic current</b>, in <a href="/wiki/Electrochemistry" title="Electrochemistry">electrochemistry</a>, is the flow of <a href="/wiki/Electron" title="Electron">electrons</a> from the cathode interface to a species in solution. The <b>anodic current</b> is the flow of electrons into the anode from a species in solution. </p> <div class="mw-heading mw-heading3"><h3 id="Electrolytic_cell">Electrolytic cell</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=4" title="Edit section: Electrolytic cell"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In an <a href="/wiki/Electrolytic_cell" title="Electrolytic cell">electrolytic cell</a>, the cathode is where the negative polarity is applied to drive the cell. Common results of reduction at the cathode are hydrogen gas or pure metal from metal ions. When discussing the relative reducing power of two redox agents, the couple for generating the more reducing species is said to be more "cathodic" with respect to the more easily reduced reagent. </p> <div class="mw-heading mw-heading3"><h3 id="Galvanic_cell">Galvanic cell</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=5" title="Edit section: Galvanic cell"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In a <a href="/wiki/Galvanic_cell" title="Galvanic cell">galvanic cell</a>, the cathode is where the positive <a href="/wiki/Electrical_polarity" class="mw-redirect" title="Electrical polarity">pole</a> is connected to allow the circuit to be completed: as the anode of the galvanic cell gives off electrons, they return from the circuit into the cell through the cathode. </p> <div class="mw-heading mw-heading3"><h3 id="Electroplating_metal_cathode_(electrolysis)"><span id="Electroplating_metal_cathode_.28electrolysis.29"></span>Electroplating metal cathode (electrolysis)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=6" title="Edit section: Electroplating metal cathode (electrolysis)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>When metal ions are reduced from ionic solution, they form a pure metal surface on the cathode. Items to be plated with pure metal are attached to and become part of the cathode in the electrolytic solution. </p> <div class="mw-heading mw-heading2"><h2 id="In_electronics">In electronics</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=7" title="Edit section: In electronics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Vacuum_tubes">Vacuum tubes</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=8" title="Edit section: Vacuum tubes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:4-1000A_linear_RF_deck_build_by_K5LAD.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e8/4-1000A_linear_RF_deck_build_by_K5LAD.jpg/220px-4-1000A_linear_RF_deck_build_by_K5LAD.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e8/4-1000A_linear_RF_deck_build_by_K5LAD.jpg/330px-4-1000A_linear_RF_deck_build_by_K5LAD.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e8/4-1000A_linear_RF_deck_build_by_K5LAD.jpg/440px-4-1000A_linear_RF_deck_build_by_K5LAD.jpg 2x" data-file-width="640" data-file-height="480" /></a><figcaption>Glow from the directly heated cathode of a 1 kW power <a href="/wiki/Tetrode" title="Tetrode">tetrode</a> tube in a radio transmitter. The cathode filament is not directly visible.</figcaption></figure> <p>In a vacuum tube or electronic vacuum system, the cathode is a metal surface which emits free electrons into the evacuated space. Since the electrons are attracted to the positive nuclei of the metal atoms, they normally stay inside the metal and require energy to leave it; this is called the <i><a href="/wiki/Work_function" title="Work function">work function</a></i> of the metal.<sup id="cite_ref-Avadhanulu_4-0" class="reference"><a href="#cite_note-Avadhanulu-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Cathodes are induced to emit electrons by several mechanisms:<sup id="cite_ref-Avadhanulu_4-1" class="reference"><a href="#cite_note-Avadhanulu-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <ul><li><i><a href="/wiki/Thermionic_emission" title="Thermionic emission">Thermionic emission</a></i>: The cathode can be heated. The increased thermal motion of the metal atoms "knocks" electrons out of the surface, an effect called thermionic emission. This technique is used in most vacuum tubes.</li> <li><i><a href="/wiki/Field_electron_emission" title="Field electron emission">Field electron emission</a></i>: A strong <a href="/wiki/Electric_field" title="Electric field">electric field</a> can be applied to the surface by placing an electrode with a high positive voltage near the cathode. The positively charged electrode attracts the electrons, causing some electrons to leave the cathode's surface.<sup id="cite_ref-Avadhanulu_4-2" class="reference"><a href="#cite_note-Avadhanulu-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> This process is used in <a href="/wiki/Cold_cathode" title="Cold cathode">cold cathodes</a> in some <a href="/wiki/Electron_microscope" title="Electron microscope">electron microscopes</a>,<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Poole_6-0" class="reference"><a href="#cite_note-Poole-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Flesch_7-0" class="reference"><a href="#cite_note-Flesch-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> and in microelectronics fabrication,<sup id="cite_ref-Poole_6-1" class="reference"><a href="#cite_note-Poole-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup></li> <li><i><a href="/wiki/Secondary_emission" title="Secondary emission">Secondary emission</a></i>: An electron, atom or molecule colliding with the surface of the cathode with enough energy can knock electrons out of the surface. These electrons are called <i>secondary electrons</i>. This mechanism is used in <a href="/wiki/Gas-discharge_lamp" title="Gas-discharge lamp">gas-discharge lamps</a> such as <a href="/wiki/Neon_lamp" title="Neon lamp">neon lamps</a>.</li> <li><i><a href="/wiki/Photoelectric_emission" class="mw-redirect" title="Photoelectric emission">Photoelectric emission</a></i>: Electrons can also be emitted from the <a href="/wiki/Electrode" title="Electrode">electrodes</a> of certain metals when light of <a href="/wiki/Frequency" title="Frequency">frequency</a> greater than the threshold frequency falls on it. This effect is called photoelectric emission, and the electrons produced are called <i>photoelectrons</i>.<sup id="cite_ref-Avadhanulu_4-3" class="reference"><a href="#cite_note-Avadhanulu-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> This effect is used in <a href="/wiki/Phototube" title="Phototube">phototubes</a> and <a href="/wiki/Image_intensifier" title="Image intensifier">image intensifier</a> tubes.</li></ul> <p>Cathodes can be divided into two types: </p> <div class="mw-heading mw-heading4"><h4 id="Hot_cathode">Hot cathode</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=9" title="Edit section: Hot cathode"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Hot_cathode" title="Hot cathode">Hot cathode</a></div> <style data-mw-deduplicate="TemplateStyles:r1237032888/mw-parser-output/.tmulti">.mw-parser-output .tmulti .multiimageinner{display:flex;flex-direction:column}.mw-parser-output .tmulti .trow{display:flex;flex-direction:row;clear:left;flex-wrap:wrap;width:100%;box-sizing:border-box}.mw-parser-output .tmulti .tsingle{margin:1px;float:left}.mw-parser-output .tmulti .theader{clear:both;font-weight:bold;text-align:center;align-self:center;background-color:transparent;width:100%}.mw-parser-output .tmulti .thumbcaption{background-color:transparent}.mw-parser-output .tmulti .text-align-left{text-align:left}.mw-parser-output .tmulti .text-align-right{text-align:right}.mw-parser-output .tmulti .text-align-center{text-align:center}@media all and (max-width:720px){.mw-parser-output .tmulti .thumbinner{width:100%!important;box-sizing:border-box;max-width:none!important;align-items:center}.mw-parser-output .tmulti .trow{justify-content:center}.mw-parser-output .tmulti .tsingle{float:none!important;max-width:100%!important;box-sizing:border-box;text-align:center}.mw-parser-output .tmulti .tsingle .thumbcaption{text-align:left}.mw-parser-output .tmulti .trow>.thumbcaption{text-align:center}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmulti .multiimageinner img{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmulti .multiimageinner img{background-color:white}}</style><div class="thumb tmulti tright"><div class="thumbinner multiimageinner" style="width:315px;max-width:315px"><div class="trow"><div class="tsingle" style="width:139px;max-width:139px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Dubulttriode_darbiibaa.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/19/Dubulttriode_darbiibaa.jpg/137px-Dubulttriode_darbiibaa.jpg" decoding="async" width="137" height="226" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/19/Dubulttriode_darbiibaa.jpg/206px-Dubulttriode_darbiibaa.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/19/Dubulttriode_darbiibaa.jpg/274px-Dubulttriode_darbiibaa.jpg 2x" data-file-width="1383" data-file-height="2279" /></a></span></div><div class="thumbcaption">Two indirectly-heated cathodes (orange heater strip) in ECC83 dual triode tube</div></div><div class="tsingle" style="width:172px;max-width:172px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Triode-english-text.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Triode-english-text.svg/170px-Triode-english-text.svg.png" decoding="async" width="170" height="226" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Triode-english-text.svg/255px-Triode-english-text.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Triode-english-text.svg/340px-Triode-english-text.svg.png 2x" data-file-width="669" data-file-height="890" /></a></span></div><div class="thumbcaption">Cutaway view of a <a href="/wiki/Triode" title="Triode">triode</a> vacuum tube with an indirectly-heated cathode <i>(orange tube)</i>, showing the heater element inside</div></div></div></div></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Triode_schematic_labeled.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/69/Triode_schematic_labeled.svg/220px-Triode_schematic_labeled.svg.png" decoding="async" width="220" height="112" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/69/Triode_schematic_labeled.svg/330px-Triode_schematic_labeled.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/69/Triode_schematic_labeled.svg/440px-Triode_schematic_labeled.svg.png 2x" data-file-width="339" data-file-height="173" /></a><figcaption><a href="/wiki/Schematic_symbol" class="mw-redirect" title="Schematic symbol">Schematic symbol</a> used in <a href="/wiki/Circuit_diagram" title="Circuit diagram">circuit diagrams</a> for vacuum tube, showing cathode</figcaption></figure> <p>A hot cathode is a cathode that is heated by a <a href="/wiki/Electrical_filament" class="mw-redirect" title="Electrical filament">filament</a> to produce electrons by <a href="/wiki/Thermionic_emission" title="Thermionic emission">thermionic emission</a>.<sup id="cite_ref-Avadhanulu_4-4" class="reference"><a href="#cite_note-Avadhanulu-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Whitaker_8-0" class="reference"><a href="#cite_note-Whitaker-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> The filament is a thin wire of a <a href="/wiki/Refractory_metal" class="mw-redirect" title="Refractory metal">refractory metal</a> like <a href="/wiki/Tungsten" title="Tungsten">tungsten</a> heated red-hot by an electric current passing through it. Before the advent of transistors in the 1960s, virtually all electronic equipment used hot-cathode <a href="/wiki/Vacuum_tube" title="Vacuum tube">vacuum tubes</a>. Today hot cathodes are used in vacuum tubes in radio transmitters and microwave ovens, to produce the electron beams in older <a href="/wiki/Cathode-ray_tube" title="Cathode-ray tube">cathode-ray tube</a> (CRT) type televisions and computer monitors, in <a href="/wiki/X-ray_generator" class="mw-redirect" title="X-ray generator">x-ray generators</a>, <a href="/wiki/Electron_microscope" title="Electron microscope">electron microscopes</a>, and <a href="/wiki/Fluorescent_tube" class="mw-redirect" title="Fluorescent tube">fluorescent tubes</a>. </p><p>There are two types of hot cathodes:<sup id="cite_ref-Avadhanulu_4-5" class="reference"><a href="#cite_note-Avadhanulu-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <ul><li><b>Directly heated cathode</b>: In this type, the filament itself is the cathode and emits the electrons directly. Directly heated cathodes were used in the first vacuum tubes, but today they are only used in <a href="/wiki/Fluorescent_tube" class="mw-redirect" title="Fluorescent tube">fluorescent tubes</a>, some large transmitting vacuum tubes, and all X-ray tubes.</li> <li><b>Indirectly heated cathode</b>: In this type, the filament is not the cathode but rather heats the cathode which then emits electrons. Indirectly heated cathodes are used in most devices today. For example, in most vacuum tubes the cathode is a nickel tube with the filament inside it, and the heat from the filament causes the outside surface of the tube to emit electrons.<sup id="cite_ref-Whitaker_8-1" class="reference"><a href="#cite_note-Whitaker-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> The filament of an indirectly heated cathode is usually called the <i>heater</i>. The main reason for using an indirectly heated cathode is to isolate the rest of the vacuum tube from the electric potential across the filament. Many vacuum tubes use <a href="/wiki/Alternating_current" title="Alternating current">alternating current</a> to heat the filament. In a tube in which the filament itself was the cathode, the alternating <a href="/wiki/Electric_field" title="Electric field">electric field</a> from the filament surface would affect the movement of the electrons and introduce hum into the tube output. It also allows the filaments in all the tubes in an electronic device to be tied together and supplied from the same current source, even though the cathodes they heat may be at different potentials.</li></ul> <p>In order to improve electron emission, cathodes are treated with chemicals, usually compounds of metals with a low <a href="/wiki/Work_function" title="Work function">work function</a>. Treated cathodes require less surface area, lower temperatures and less power to supply the same cathode current. The untreated tungsten filaments used in early tubes (called "bright emitters") had to be heated to 1,400 °C (2,550 °F), white-hot, to produce sufficient thermionic emission for use, while modern coated cathodes produce far more electrons at a given temperature so they only have to be heated to 425–600 °C (797–1,112 °F)<sup id="cite_ref-Avadhanulu_4-6" class="reference"><a href="#cite_note-Avadhanulu-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-IanPoole_9-0" class="reference"><a href="#cite_note-IanPoole-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Jones_10-0" class="reference"><a href="#cite_note-Jones-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> There are two main types of treated cathodes:<sup id="cite_ref-Avadhanulu_4-7" class="reference"><a href="#cite_note-Avadhanulu-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Whitaker_8-2" class="reference"><a href="#cite_note-Whitaker-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Neon_lamp_on_DC.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Neon_lamp_on_DC.JPG/110px-Neon_lamp_on_DC.JPG" decoding="async" width="110" height="222" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Neon_lamp_on_DC.JPG/165px-Neon_lamp_on_DC.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Neon_lamp_on_DC.JPG/220px-Neon_lamp_on_DC.JPG 2x" data-file-width="228" data-file-height="461" /></a><figcaption>Cold cathode <i>(lefthand electrode)</i> in <a href="/wiki/Neon_lamp" title="Neon lamp">neon lamp</a> </figcaption></figure> <ul><li>Coated cathode – In these the cathode is covered with a coating of <a href="/wiki/Alkali_metal" title="Alkali metal">alkali metal</a> oxides, often <a href="/wiki/Barium" title="Barium">barium</a> and <a href="/wiki/Strontium" title="Strontium">strontium</a> oxide. These are used in low-power tubes.</li> <li>Thoriated tungsten – In high-power tubes, <a href="/wiki/Ion" title="Ion">ion</a> bombardment can destroy the coating on a coated cathode. In these tubes a directly heated cathode consisting of a filament made of tungsten incorporating a small amount of <a href="/wiki/Thorium" title="Thorium">thorium</a> is used. The layer of thorium on the surface which reduces the work function of the cathode is continually replenished as it is lost by diffusion of thorium from the interior of the metal.<sup id="cite_ref-Sisodia_11-0" class="reference"><a href="#cite_note-Sisodia-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading4"><h4 id="Cold_cathode">Cold cathode</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=10" title="Edit section: Cold cathode"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Cold_cathode" title="Cold cathode">Cold cathode</a></div> <p>This is a cathode that is not heated by a filament. They may emit electrons by <a href="/wiki/Field_electron_emission" title="Field electron emission">field electron emission</a>, and in gas-filled tubes by <a href="/wiki/Secondary_emission" title="Secondary emission">secondary emission</a>. Some examples are electrodes in <a href="/wiki/Neon_light" class="mw-redirect" title="Neon light">neon lights</a>, <a href="/wiki/Cold-cathode_fluorescent_lamp" class="mw-redirect" title="Cold-cathode fluorescent lamp">cold-cathode fluorescent lamps</a> (CCFLs) used as backlights in laptops, <a href="/wiki/Thyratron" title="Thyratron">thyratron</a> tubes, and <a href="/wiki/Crookes_tube" title="Crookes tube">Crookes tubes</a>. They do not necessarily operate at room temperature; in some devices the cathode is heated by the electron current flowing through it to a temperature at which <a href="/wiki/Thermionic_emission" title="Thermionic emission">thermionic emission</a> occurs. For example, in some fluorescent tubes a momentary high voltage is applied to the electrodes to start the current through the tube; after starting the electrodes are heated enough by the current to keep emitting electrons to sustain the discharge.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2024)">citation needed</span></a></i>]</sup> </p><p>Cold cathodes may also emit electrons by <a href="/wiki/Photoelectric_emission" class="mw-redirect" title="Photoelectric emission">photoelectric emission</a>. These are often called <i>photocathodes</i> and are used in <a href="/wiki/Phototube" title="Phototube">phototubes</a> used in scientific instruments and <a href="/wiki/Image_intensifier" title="Image intensifier">image intensifier</a> tubes used in night vision goggles.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2024)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading3"><h3 id="Diodes">Diodes</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=11" title="Edit section: Diodes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Diode_symbol.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b4/Diode_symbol.svg/220px-Diode_symbol.svg.png" decoding="async" width="220" height="94" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b4/Diode_symbol.svg/330px-Diode_symbol.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b4/Diode_symbol.svg/440px-Diode_symbol.svg.png 2x" data-file-width="140" data-file-height="60" /></a><figcaption></figcaption></figure> <p>In a <a href="/wiki/Semiconductor_device" title="Semiconductor device">semiconductor</a> <a href="/wiki/Diode" title="Diode">diode</a>, the cathode is the <a href="/wiki/Doping_(semiconductor)" title="Doping (semiconductor)">N–doped</a> layer of the <a href="/wiki/P%E2%80%93n_junction" title="P–n junction">p–n junction</a> with a high density of free electrons due to doping, and an equal density of fixed positive charges, which are the dopants that have been thermally ionized. In the anode, the converse applies: It features a high density of free "holes" and consequently fixed negative dopants which have captured an electron (hence the origin of the holes).<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2024)">citation needed</span></a></i>]</sup> </p><p>When P and N-doped layers are created adjacent to each other, diffusion ensures that electrons flow from high to low density areas: That is, from the N to the P side. They leave behind the fixed positively charged dopants near the junction. Similarly, holes diffuse from P to N leaving behind fixed negative ionised dopants near the junction. These layers of fixed positive and negative charges are collectively known as the depletion layer because they are depleted of free electrons and holes. The depletion layer at the junction is at the origin of the diode's rectifying properties. This is due to the resulting internal field and corresponding potential barrier which inhibit current flow in reverse applied bias which increases the internal depletion layer field. Conversely, they allow it in forwards applied bias where the applied bias reduces the built in potential barrier. </p><p>Electrons which diffuse from the cathode into the P-doped layer, or anode, become what are termed "minority carriers" and tend to recombine there with the majority carriers, which are holes, on a timescale characteristic of the material which is the p-type minority carrier lifetime. Similarly, holes diffusing into the N-doped layer become minority carriers and tend to recombine with electrons. In equilibrium, with no applied bias, thermally assisted diffusion of electrons and holes in opposite directions across the depletion layer ensure a zero net current with electrons flowing from cathode to anode and recombining, and holes flowing from anode to cathode across the junction or depletion layer and recombining.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2024)">citation needed</span></a></i>]</sup> </p><p>Like a typical diode, there is a fixed anode and cathode in a Zener diode, but it will conduct current in the reverse direction (electrons flow from anode to cathode) if its breakdown voltage or "Zener voltage" is exceeded.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2024)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=12" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col"> <ul><li><a href="/wiki/Battery_(electricity)" class="mw-redirect" title="Battery (electricity)">Battery</a></li> <li><a href="/wiki/Cathode_bias" title="Cathode bias">Cathode bias</a></li> <li><a href="/wiki/Cathodic_protection" title="Cathodic protection">Cathodic protection</a></li> <li><a href="/wiki/Electrolysis" title="Electrolysis">Electrolysis</a></li> <li><a href="/wiki/Electrolytic_cell" title="Electrolytic cell">Electrolytic cell</a></li> <li><a href="/wiki/Gas-filled_tube" title="Gas-filled tube">Gas-filled tube</a></li> <li><a href="/wiki/Oxidation-reduction" class="mw-redirect" title="Oxidation-reduction">Oxidation-reduction</a></li> <li><a href="/wiki/Poly(3,4-ethylenedioxythiophene)" title="Poly(3,4-ethylenedioxythiophene)">PEDOT</a></li> <li><a href="/wiki/Vacuum_tube" title="Vacuum tube">Vacuum tube</a></li></ul> </div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=13" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-Reversed_Daniell_Cell-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-Reversed_Daniell_Cell_1-0">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external autonumber" href="http://hyperphysics.phy-astr.gsu.edu/hbase/chemical/electrolyt.html#c1">[1]</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20110604135153/http://hyperphysics.phy-astr.gsu.edu/HBASE/Chemical/electrolyt.html">Archived</a> 4 June 2011 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a>, Daniell cell can be reversed to, technically, produce an electrolytic cell.</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFRoss1961" class="citation journal cs1">Ross, S (1 November 1961). "Faraday consults the scholars: the origins of the terms of electrochemistry". <i>Notes and Records of the Royal Society of London</i>. <b>16</b> (2): 187–220. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1098%2Frsnr.1961.0038">10.1098/rsnr.1961.0038</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:145600326">145600326</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Notes+and+Records+of+the+Royal+Society+of+London&rft.atitle=Faraday+consults+the+scholars%3A+the+origins+of+the+terms+of+electrochemistry&rft.volume=16&rft.issue=2&rft.pages=187-220&rft.date=1961-11-01&rft_id=info%3Adoi%2F10.1098%2Frsnr.1961.0038&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A145600326%23id-name%3DS2CID&rft.aulast=Ross&rft.aufirst=S&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFaraday1849" class="citation book cs1"><a href="/wiki/Michael_Faraday" title="Michael Faraday">Faraday, Michael</a> (1849). <a rel="nofollow" class="external text" href="http://www.gutenberg.org/files/14986/14986-h/14986-h.htm"><i>Experimental Researches In Electricity</i></a>. Vol. 1. London: The University of London.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Experimental+Researches+In+Electricity&rft.place=London&rft.pub=The+University+of+London&rft.date=1849&rft.aulast=Faraday&rft.aufirst=Michael&rft_id=http%3A%2F%2Fwww.gutenberg.org%2Ffiles%2F14986%2F14986-h%2F14986-h.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-Avadhanulu-4"><span class="mw-cite-backlink">^ <a href="#cite_ref-Avadhanulu_4-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Avadhanulu_4-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Avadhanulu_4-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Avadhanulu_4-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Avadhanulu_4-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Avadhanulu_4-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Avadhanulu_4-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Avadhanulu_4-7"><sup><i><b>h</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAvadhanuluP.G._Kshirsagar1992" class="citation book cs1">Avadhanulu, M.N.; P.G. Kshirsagar (1992). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=lTUNWOR_cDgC&pg=PA345"><i>A Textbook Of Engineering Physics For B.E., B.Sc</i></a>. S. Chand. pp. 345–348. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-8121908177" title="Special:BookSources/978-8121908177"><bdi>978-8121908177</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140102024212/http://books.google.com/books?id=lTUNWOR_cDgC&pg=PA345">Archived</a> from the original on 2 January 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=A+Textbook+Of+Engineering+Physics+For+B.E.%2C+B.Sc.&rft.pages=345-348&rft.pub=S.+Chand&rft.date=1992&rft.isbn=978-8121908177&rft.aulast=Avadhanulu&rft.aufirst=M.N.&rft.au=P.G.+Kshirsagar&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DlTUNWOR_cDgC%26pg%3DPA345&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation encyclopaedia cs1"><a rel="nofollow" class="external text" href="https://www.britannica.com/EBchecked/topic/206253/field-emission">"Field emission"</a>. <i>Encyclopædia Britannica online</i>. 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Retrieved <span class="nowrap">15 March</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Field+emission&rft.btitle=Encyclop%C3%A6dia+Britannica+online&rft.pub=Encyclop%C3%A6dia+Britannica%2C+Inc.&rft.date=2014&rft_id=https%3A%2F%2Fwww.britannica.com%2FEBchecked%2Ftopic%2F206253%2Ffield-emission&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-Poole-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-Poole_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Poole_6-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPoole2004" class="citation book cs1">Poole, Charles P. 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Academic Press. p. 468. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0080545233" title="Special:BookSources/978-0080545233"><bdi>978-0080545233</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20171224222803/https://books.google.com/books?id=CXwrqM2hU0EC&pg=PA468&dq=field+electron+emission">Archived</a> from the original on 24 December 2017.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Encyclopedic+Dictionary+of+Condensed+Matter+Physics%2C+Vol.+1&rft.pages=468&rft.pub=Academic+Press&rft.date=2004&rft.isbn=978-0080545233&rft.aulast=Poole&rft.aufirst=Charles+P.+Jr.&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DCXwrqM2hU0EC%26q%3Dfield%2Belectron%2Bemission%26pg%3DPA468&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-Flesch-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-Flesch_7-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFlesch2007" class="citation book cs1">Flesch, Peter G. (2007). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=fWHQbhgxpAkC&pg=PA102"><i>Light and Light Sources: High-Intensity Discharge Lamps</i></a>. Springer. pp. 102–103. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-3540326854" title="Special:BookSources/978-3540326854"><bdi>978-3540326854</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20171224222803/https://books.google.com/books?id=fWHQbhgxpAkC&pg=PA102">Archived</a> from the original on 24 December 2017.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Light+and+Light+Sources%3A+High-Intensity+Discharge+Lamps&rft.pages=102-103&rft.pub=Springer&rft.date=2007&rft.isbn=978-3540326854&rft.aulast=Flesch&rft.aufirst=Peter+G.&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DfWHQbhgxpAkC%26pg%3DPA102&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-Whitaker-8"><span class="mw-cite-backlink">^ <a href="#cite_ref-Whitaker_8-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Whitaker_8-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Whitaker_8-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text">Ferris, Clifford "Electron tube fundamentals" in <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWhitaker2013" class="citation book cs1">Whitaker, Jerry C. (2013). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=FdSQSAC3_EwC&pg=PA355"><i>The Electronics Handbook, 2nd Ed</i></a>. CRC Press. pp. 354–356. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1420036664" title="Special:BookSources/978-1420036664"><bdi>978-1420036664</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140102024350/http://books.google.com/books?id=FdSQSAC3_EwC&pg=PA355">Archived</a> from the original on 2 January 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+Electronics+Handbook%2C+2nd+Ed.&rft.pages=354-356&rft.pub=CRC+Press&rft.date=2013&rft.isbn=978-1420036664&rft.aulast=Whitaker&rft.aufirst=Jerry+C.&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DFdSQSAC3_EwC%26pg%3DPA355&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-IanPoole-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-IanPoole_9-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPoole2012" class="citation web cs1">Poole, Ian (2012). <a rel="nofollow" class="external text" href="http://www.radio-electronics.com/info/data/thermionic-valves/vacuum-tube-theory/tube-electrodes.php">"Vacuum tube electrodes"</a>. <i>Vacuum Tube Theory Basics Tutorial</i>. Radio-Electronics.com, Adrio Communications. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20131104104630/http://www.radio-electronics.com/info/data/thermionic-valves/vacuum-tube-theory/tube-electrodes.php">Archived</a> from the original on 4 November 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">3 October</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Vacuum+Tube+Theory+Basics+Tutorial&rft.atitle=Vacuum+tube+electrodes&rft.date=2012&rft.aulast=Poole&rft.aufirst=Ian&rft_id=http%3A%2F%2Fwww.radio-electronics.com%2Finfo%2Fdata%2Fthermionic-valves%2Fvacuum-tube-theory%2Ftube-electrodes.php&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-Jones-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-Jones_10-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJones1995" class="citation book cs1">Jones, Martin Hartley (1995). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=EEcemABAU44C&pg=PA49"><i>A Practical Introduction to Electronic Circuits</i></a>. UK: Cambridge Univ. Press. p. 49. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0521478793" title="Special:BookSources/978-0521478793"><bdi>978-0521478793</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140102024515/http://books.google.com/books?id=EEcemABAU44C&pg=PA49">Archived</a> from the original on 2 January 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=A+Practical+Introduction+to+Electronic+Circuits&rft.place=UK&rft.pages=49&rft.pub=Cambridge+Univ.+Press&rft.date=1995&rft.isbn=978-0521478793&rft.aulast=Jones&rft.aufirst=Martin+Hartley&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DEEcemABAU44C%26pg%3DPA49&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> <li id="cite_note-Sisodia-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-Sisodia_11-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSisodia2006" class="citation book cs1">Sisodia, M. L. (2006). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=mKs53pET-bkC&pg=SA2-PA4"><i>Microwave Active Devices Vacuum and Solid State</i></a>. New Age International. p. 2.5. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-8122414479" title="Special:BookSources/978-8122414479"><bdi>978-8122414479</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140102024156/http://books.google.com/books?id=mKs53pET-bkC&pg=SA2-PA4">Archived</a> from the original on 2 January 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Microwave+Active+Devices+Vacuum+and+Solid+State&rft.pages=2.5&rft.pub=New+Age+International&rft.date=2006&rft.isbn=978-8122414479&rft.aulast=Sisodia&rft.aufirst=M.+L.&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DmKs53pET-bkC%26pg%3DSA2-PA4&rfr_id=info%3Asid%2Fen.wikipedia.org%3ACathode" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Cathode&action=edit&section=14" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.crtsite.com">The Cathode Ray Tube site</a></li> <li><a rel="nofollow" class="external text" href="http://www.av8n.com/physics/anode-cathode.htm">How to define anode and cathode</a></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl 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cell">Chromic acid</a></li> <li><a href="/wiki/Clark_cell" title="Clark cell">Clark</a></li> <li><a href="/wiki/Daniell_cell" title="Daniell cell">Daniell</a></li> <li><a href="/wiki/Dry_cell" title="Dry cell">Dry</a></li> <li><a href="/wiki/Edison%E2%80%93Lalande_cell" title="Edison–Lalande cell">Edison–Lalande</a></li> <li><a href="/wiki/Grove_cell" title="Grove cell">Grove</a></li> <li><a href="/wiki/Leclanch%C3%A9_cell" title="Leclanché cell">Leclanché</a></li> <li><a href="/wiki/Lithium_metal_battery" title="Lithium metal battery">Lithium metal</a></li> <li><a href="/wiki/Lithium%E2%80%93air_battery" title="Lithium–air battery">Lithium–air</a></li> <li><a href="/wiki/Mercury_battery" title="Mercury battery">Mercury</a></li> <li><a href="/wiki/Metal%E2%80%93air_electrochemical_cell" title="Metal–air electrochemical cell">Metal–air electrochemical</a></li> <li><a href="/wiki/Nickel_oxyhydroxide_battery" title="Nickel oxyhydroxide battery">Nickel oxyhydroxide</a></li> <li><a href="/wiki/Silicon%E2%80%93air_battery" title="Silicon–air battery">Silicon–air</a></li> <li><a href="/wiki/Silver_oxide_battery" title="Silver oxide battery">Silver oxide</a></li> <li><a href="/wiki/Weston_cell" title="Weston cell">Weston</a></li> <li><a href="/wiki/Zamboni_pile" title="Zamboni pile">Zamboni</a></li> <li><a href="/wiki/Zinc%E2%80%93air_battery" title="Zinc–air battery">Zinc–air</a></li> <li><a href="/wiki/Zinc%E2%80%93carbon_battery" title="Zinc–carbon battery">Zinc–carbon</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;"><a href="/wiki/Rechargeable_battery" title="Rechargeable battery">Secondary cell</a><br /><span class="nobold">(rechargeable)</span></div></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Automotive_battery" title="Automotive battery">Automotive</a></li> <li><a href="/wiki/Lead%E2%80%93acid_battery" title="Lead–acid battery">Lead–acid</a> <ul><li><a href="/wiki/VRLA_battery" title="VRLA battery">gel–VRLA</a></li></ul></li> <li><a href="/wiki/Lithium%E2%80%93air_battery" title="Lithium–air battery">Lithium–air</a></li> <li><a href="/wiki/Lithium-ion_battery" title="Lithium-ion battery">Lithium ion</a> <ul><li><a href="/wiki/Dual_carbon_battery" title="Dual carbon battery">Dual carbon</a></li> <li><a href="/wiki/Lithium_iron_phosphate_battery" title="Lithium iron phosphate battery">Lithium–iron–phosphate</a></li> <li><a href="/wiki/Lithium_polymer_battery" title="Lithium polymer battery">Lithium–polymer</a></li> <li><a href="/wiki/Lithium%E2%80%93sulfur_battery" title="Lithium–sulfur battery">Lithium–sulfur</a></li> <li><a href="/wiki/Lithium-titanate_battery" title="Lithium-titanate battery">Lithium–titanate</a></li></ul></li> <li><a href="/wiki/Metal%E2%80%93air_electrochemical_cell" title="Metal–air electrochemical cell">Metal–air</a></li> <li><a href="/wiki/Molten-salt_battery" title="Molten-salt battery">Molten salt</a></li> <li><a href="/wiki/Nanopore_battery" title="Nanopore battery">Nanopore</a></li> <li><a href="/wiki/Nanowire_battery" title="Nanowire battery">Nanowire</a></li> <li><a href="/wiki/Nickel%E2%80%93cadmium_battery" title="Nickel–cadmium battery">Nickel–cadmium</a></li> <li><a href="/wiki/Nickel%E2%80%93hydrogen_battery" title="Nickel–hydrogen battery">Nickel–hydrogen</a></li> <li><a href="/wiki/Nickel%E2%80%93iron_battery" title="Nickel–iron battery">Nickel–iron</a></li> <li><a href="/wiki/Nickel%E2%80%93lithium_battery" title="Nickel–lithium battery">Nickel–lithium</a></li> <li><a href="/wiki/Nickel%E2%80%93metal_hydride_battery" title="Nickel–metal hydride battery">Nickel–metal hydride</a></li> <li><a href="/wiki/Nickel%E2%80%93zinc_battery" title="Nickel–zinc battery">Nickel–zinc</a></li> <li><a href="/wiki/Polysulfide%E2%80%93bromide_battery" title="Polysulfide–bromide battery">Polysulfide–bromide</a></li> <li><a href="/wiki/Potassium-ion_battery" title="Potassium-ion battery">Potassium ion</a></li> <li><a href="/wiki/Rechargeable_alkaline_battery" title="Rechargeable alkaline battery">Rechargeable alkaline</a></li> <li><a href="/wiki/Silver%E2%80%93cadmium_battery" title="Silver–cadmium battery">Silver–cadmium</a></li> <li><a href="/wiki/Silver_zinc_battery" title="Silver zinc battery">Silver–zinc</a></li> <li><a href="/wiki/Sodium-ion_battery" title="Sodium-ion battery">Sodium ion</a></li> <li><a href="/wiki/Sodium%E2%80%93sulfur_battery" title="Sodium–sulfur battery">Sodium–sulfur</a></li> <li><a href="/wiki/Solid-state_battery" title="Solid-state battery">Solid state</a></li> <li><a href="/wiki/Vanadium_redox_battery" title="Vanadium redox battery">Vanadium redox</a></li> <li><a href="/wiki/Zinc%E2%80%93bromine_battery" title="Zinc–bromine battery">Zinc–bromine</a></li> <li><a href="/wiki/Zinc%E2%80%93cerium_battery" title="Zinc–cerium battery">Zinc–cerium</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Other cell</div></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Atomic_battery" title="Atomic battery">Atomic battery</a></li> <li><a href="/wiki/Fuel_cell" title="Fuel cell">Fuel cell</a></li> <li><a href="/wiki/Solar_cell" title="Solar cell">Solar cell</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Cell parts</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Anode" title="Anode">Anode</a></li> <li><a href="/wiki/Binder_(material)" title="Binder (material)">Binder</a></li> <li><a href="/wiki/Catalysis" title="Catalysis">Catalyst</a></li> <li><a class="mw-selflink selflink">Cathode</a></li> <li><a href="/wiki/Electrode" title="Electrode">Electrode</a></li> <li><a href="/wiki/Electrolyte" title="Electrolyte">Electrolyte</a></li> <li><a href="/wiki/Half-cell" title="Half-cell">Half-cell</a></li> <li><a href="/wiki/Ion" title="Ion">Ions</a></li> <li><a href="/wiki/Salt_bridge" title="Salt bridge">Salt bridge</a></li> <li><a href="/wiki/Semipermeable_membrane" title="Semipermeable membrane">Semipermeable membrane</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox authority-control" aria-label="Navbox" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a 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