{"id":1270,"date":"2026-03-20T10:44:17","date_gmt":"2026-03-20T10:44:17","guid":{"rendered":"https:\/\/citations.tools.bio-logic.fr\/?p=1270"},"modified":"2026-03-20T10:44:17","modified_gmt":"2026-03-20T10:44:17","slug":"understanding-the-oxygen-evolution-reaction-mechanism-on-coox-using-operando-ambient-pressure-x-ray-photoelectron-spectroscopy","status":"publish","type":"post","link":"https:\/\/citations.tools.bio-logic.fr\/?p=1270","title":{"rendered":"Understanding the Oxygen Evolution Reaction Mechanism on CoO<sub><i>x<\/i><\/sub> using <i>Operando<\/i> Ambient-Pressure X-ray Photoelectron Spectroscopy"},"content":{"rendered":"<h4>DOI:<\/h4>\n<p><a href=\"https:\/\/doi.org\/10.1021\/jacs.7b03211\" target=\"_blank\" rel=\"noopener\">10.1021\/jacs.7b03211<\/a><\/p>\n<h4>Authors:<\/h4>\n<p>Marco Favaro, Jinhui Yang, Silvia Nappini, Elena Magnano, Francesca M. Toma, Ethan J. Crumlin, Junko Yano, Ian D. Sharp<\/p>\n<h4>Abstract:<\/h4>\n<p>Photoelectrochemical water splitting is a promising approach for renewable production of hydrogen from solar energy and requires interfacing advanced water-splitting catalysts with semiconductors. Understanding the mechanism of function of such electrocatalysts at the atomic scale and under realistic working conditions is a challenging, yet important, task for advancing efficient and stable function. This is particularly true for the case of oxygen evolution catalysts and, here, we study a highly active Co<sub>3<\/sub>O<sub>4<\/sub>\/Co(OH)<sub>2<\/sub> biphasic electrocatalyst on Si by means of operando ambient-pressure X-ray photoelectron spectroscopy performed at the solid\/liquid electrified interface. Spectral simulation and multiplet fitting reveal that the catalyst undergoes chemical-structural transformations as a function of the applied anodic potential, with complete conversion of the Co(OH)<sub>2<\/sub> and partial conversion of the spinel Co<sub>3<\/sub>O<sub>4<\/sub> phases to CoO(OH) under precatalytic electrochemical conditions. Furthermore, we observe new spectral features in both Co 2p and O 1s core-level regions to emerge under oxygen evolution reaction conditions on CoO(OH). The operando photoelectron spectra support assignment of these newly observed features to highly active Co<sup>4+<\/sup> centers under catalytic conditions. Comparison of these results to those from a pure phase spinel Co<sub>3<\/sub>O<sub>4<\/sub> catalyst supports this interpretation and reveals that the presence of Co(OH)<sub>2<\/sub> enhances catalytic activity by promoting transformations to CoO(OH). The direct investigation of electrified interfaces presented in this work can be extended to different materials under realistic catalytic conditions, thereby providing a powerful tool for mechanism discovery and an enabling capability for catalyst design.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>DOI: 10.1021\/jacs.7b03211 Authors: Marco Favaro, Jinhui Yang, Silvia Nappini, Elena Magnano, Francesca M. Toma, Ethan J. Crumlin, Junko Yano, Ian D. Sharp Abstract: Photoelectrochemical water splitting is a promising approach for renewable production of hydrogen from solar energy and requires interfacing advanced water-splitting catalysts with semiconductors. Understanding the mechanism of function of such electrocatalysts at [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[27],"tags":[],"class_list":["post-1270","post","type-post","status-publish","format-standard","hentry","category-sp-300-potentiostat"],"_links":{"self":[{"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/posts\/1270","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1270"}],"version-history":[{"count":0,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=\/wp\/v2\/posts\/1270\/revisions"}],"wp:attachment":[{"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1270"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1270"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/citations.tools.bio-logic.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1270"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}