Institute for Tenure Track Promotion, University of Miyazaki, Nishi 1-1 Gakuen-Kibanadai, Miyazaki, 889-2192, Japan.
Global Zero Emission Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 16-1 Onogawa, Ibaraki, 305-8569, Japan.
Chemistry. 2023 Apr 25;29(24):e202204058. doi: 10.1002/chem.202204058. Epub 2023 Mar 20.
The hydrogen evolution reaction (HER) of Rh nanoparticles (RhNP) coated with an ultrathin layer of Cr-oxides (CrO ) was investigated as a model electrode for the Cr O /Rh-metal core-shell-type cocatalyst system for photocatalytic water splitting. The CrO layer was electrodeposited over RhNP on a transparent conductive fluorine-doped tin oxide (FTO) substrate. The CrO layer on RhNP facilitates the electron transfer process at the CrO /RhNP interface, leading to the increased current density for the HER. Impedance spectroscopic analysis revealed that the CrO layer transferred protons via the hopping mechanism to the RhNP surface for HER. In addition, CrO restricted electron transfer from the FTO to the electrolyte and/or RhNP and suppressed the backward reaction by limiting oxygen migration. This study clarifies the crucial role of the ultrathin CrO layer on nanoparticulate cocatalysts and provides a cocatalyst design strategy for realizing efficient photocatalytic water splitting.
研究了包覆在超薄 Cr 氧化物 (CrO )层上的 Rh 纳米粒子 (RhNP) 的析氢反应 (HER)，作为 Cr O /Rh 金属核壳型共催化剂系统用于光催化水分解的模型电极。CrO 层通过电沉积在透明导电掺氟氧化锡 (FTO) 基底上的 RhNP 上。RhNP 上的 CrO 层促进了 CrO /RhNP 界面处的电子转移过程，导致 HER 的电流密度增加。阻抗谱分析表明，CrO 层通过跳跃机制将质子转移到 RhNP 表面用于 HER。此外，CrO 限制了电子从 FTO 向电解质和/或 RhNP 的转移，并通过限制氧迁移来抑制逆向反应。这项研究阐明了纳米颗粒共催化剂上超薄 CrO 层的关键作用，并为实现高效光催化水分解提供了共催化剂设计策略。
