{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,30]],"date-time":"2026-10-30T19:34:06Z","timestamp":1793388846012,"version":"4.5.0"},"reference-count":28,"publisher":"Oxford University Press (OUP)","issue":"8","license":[{"start":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T00:00:00Z","timestamp":1770595200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22122903"],"award-info":[{"award-number":["22122903"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52072187"],"award-info":[{"award-number":["52072187"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Tianjin Distinguished Young Scholars Fund","award":["20JCJQJC00260"],"award-info":[{"award-number":["20JCJQJC00260"]}]},{"name":"Scientific Research Innovation Capability Support Project for Young Faculty"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,4,27]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>Photoelectrochemical carbon dioxide reduction (PEC CO2R) enables direct solar-to-chemical conversion. However, few photocathodes are intrinsically stable light absorbers. The application of protective layers remains a critical approach for stabilizing photocathodes in corrosive environments. TiO2 is the most widely adopted stabilizer, yet its influence on catalytic performance remains poorly understood. Here, we examine TiO2-protected Cu2O photocathodes integrated with Au, Cu and Bi cocatalysts, combining experiments and simulations to unravel the role of the TiO2 overlayer. We find that TiO2 profoundly alters catalytic selectivity, suppressing CO and multicarbon (C2+) pathways, while its impact on formate production with Bi, In and Sn cocatalysts is comparatively negligible. These results demonstrate that TiO2 is not an inert stabilizer, but an active component that reshapes interfacial reaction pathways. This work establishes critical design principles for integrating protective layers with photocathodes to achieve selective and efficient PEC CO2R.<\/jats:p>","DOI":"10.1093\/nsr\/nwag092","type":"journal-article","created":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T12:36:18Z","timestamp":1770640578000},"source":"Crossref","is-referenced-by-count":3,"title":["TiO2 protective layers shape photocathode performance in photoelectrochemical CO2 reduction"],"prefix":"10.1093","volume":"13","author":[{"given":"Linxiao","family":"Wu","sequence":"first","affiliation":[{"name":"Institute of Photoelectronic Thin Film Devices and Technology, State Key Laboratory of Photovoltaic Materials and Cells, Tianjin Key Laboratory of Efficient Solar Energy Utilization, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Nankai University , Tianjin 300350 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yumeng","family":"Han","sequence":"additional","affiliation":[{"name":"Institute of Photoelectronic Thin Film Devices and Technology, State Key Laboratory of Photovoltaic Materials and Cells, Tianjin Key Laboratory of Efficient Solar Energy Utilization, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Nankai University , Tianjin 300350 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hao","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Photoelectronic Thin Film Devices and Technology, State Key Laboratory of Photovoltaic Materials and Cells, Tianjin Key Laboratory of Efficient Solar Energy Utilization, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Nankai University , Tianjin 300350 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peixuan","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Electronic Information and Optical Engineering, Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Nankai University , Tianjin 300350 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinshui","family":"Cheng","sequence":"additional","affiliation":[{"name":"Institute of Photoelectronic Thin Film Devices and Technology, State Key Laboratory of Photovoltaic Materials and Cells, Tianjin Key Laboratory of Efficient Solar Energy Utilization, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Nankai University , Tianjin 300350 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bin","family":"Shao","sequence":"additional","affiliation":[{"name":"College of Electronic Information and Optical Engineering, Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Nankai University , Tianjin 300350 ,","place":["China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1770-7681","authenticated-orcid":false,"given":"Jingshan","family":"Luo","sequence":"additional","affiliation":[{"name":"Institute of Photoelectronic Thin Film Devices and Technology, State Key Laboratory of Photovoltaic Materials and Cells, Tianjin Key Laboratory of Efficient Solar Energy Utilization, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Nankai University , Tianjin 300350 ,","place":["China"]},{"name":"Frontiers Science Center for New Organic Matter, Nankai University , Tianjin 300071 ,","place":["China"]},{"name":"Academy for Advanced Interdisciplinary Studies, Nankai University , Tianjin 300071 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