文献类型：期刊文献

英文题名：Disentangling the activity-charge coupling in cocatalyst-semiconductor heterojunctions for optimized oxygen evolution

作者：Liu, Ying[1];Zhou, Min[1];Ren, Guanhua[1];Hu, Peijun[2,3];Wang, Haifeng[1]

机构：[1]East China Univ Sci & Technol, Ctr Computat Chem & Res, State Key Lab Green Chem Engn & Ind Catalysis, Inst Ind Catalysis, Shanghai 200237, Peoples R China;[2]Queens Univ Belfast, Sch Chem & Chem Engn, Belfast BT9 5AG, North Ireland;[3]ShanghaiTech Univ, Sch Phys Sci & Technol, Shanghai 201210, Peoples R China

年份：2026

外文期刊名：ENERGY & ENVIRONMENTAL SCIENCE

收录：;EI(收录号：20262420890065);WOS:【SCI-EXPANDED(收录号:WOS:001790006900001)】；

基金：This project was supported by the National Key R&D Program of China (2021YFA1500700), the NSFC (22525202 and 22202069), the Special Support by the China Postdoctoral Science Foundation (in front of the website) (2022TQ0106), the China Postdoctoral Science Foundation Funded Project (2022M721141), and the Fundamental Research Funds for the Central University.

语种：英文

外文关键词：Activation analysis - Catalyst activity - Chromium compounds - Hole concentration - Iridium compounds - Metal analysis - Molecular oxygen - Oxide minerals - Oxygen evolution reaction - Photocatalysts - Photocatalytic activity - Photoelectricity - Rhodium compounds

摘要：Decoupling cocatalyst effects in photocatalysis, often intertwined between enhancing photocarrier accumulation and boosting intrinsic catalytic activity (ICA), is essential yet challenging for the rational design of photocatalysts. Using the cocatalyst-IrO2/TiO2 heterojunction as a prototype, we integrate ab initio molecular dynamics with first-principles microkinetic modeling to elucidate the oxygen evolution reaction (OER) mechanism at the aqueous interface under varying light intensities. Our analysis reveals how IrO2 modulates photo-hole harvesting to regulate water activation and O-O coupling, enabling a quantitative separation of ICA from cocatalyst-mediated effects. Surprisingly, IrO2/TiO2 does not exceed bare TiO2 in ICA, as excessively strong oxygen binding at surface Ir sites hinders O-O bond formation. Instead, the enhanced O2 turnover originates from an increased surface hole concentration, facilitated by the superior hole accumulation capacity (HAC) of IrO2 and the formation of a Schottky junction, which compensate for its limited ICA. Extending this analysis to rutile-type metal oxide cocatalysts with varying oxygen affinities uncovers an intrinsic ICA-HAC seesaw relationship that gives rise to a volcano-type OER activity trend. We further identify the work function (phi m) as a unifying descriptor, with moderate-phi m cocatalysts (e.g., RhO2 and CrO2) predicted to deliver optimal performance by balancing these competing effects. This study provides the first quantitative disentanglement of cocatalyst functions, establishing a general design principle for efficient OER cocatalysts.