析氧助催化剂表面活性位调控增强光电催化分解水性能研究

在太阳能光电催化分解水反应体系中，光阳极表面选择性构建析氧助催化剂（OEC）被广泛用于提高光电催化性能，然而对于OEC表面催化活性位的深入研究与理性调控未受到关注。本项目拟通过构建超薄结构、表面氧缺陷引入、元素掺杂、选择性界面键合等一系列策略对OEC表面活性位进行合理调控，有效促进光生空穴快速转移至OEC表面参与水氧化反应，大幅度提高太阳能光电催化分解水活性及转化效率。此外，利用协同光照-X射线光电子能谱、瞬态吸收光谱对激发态下光生电荷的转移路径进行观测研究，通过密度泛函理论对OEC表面吸附能、电荷密度分布、水氧化动力学过程等进行理论研究，结合实验和理论结果阐明OEC表面活性位提升光电催化性能的作用机制，为太阳能光催化及光电催化分解水研究提供实验和理论依据。

In the solar photoelectrocatalytic water splitting reaction system, the selective construction of oxygen evolution cocatalyst (OEC) on the surface of photoanode was widely used to improve the water oxidation performance. However, the in-depth research and rational regulation of the catalytic active sites on the surface of OEC have not received much attention. Therefore, this project intends to regulate rationally the surface active sites of the OEC through a series of strategies such as constructing ultrathin structure, introducing surface oxygen defects, element doping, and selective interface bonding, which could effectively accelerate the transfer of photogenerated holes to the surface of oxygen evolution cocatalyst to participate in the water oxidation reaction, thus improving greatly the catalytic activity and photoelectronic conversion efficiency of solar photoelectrocatalytic water splitting. Furthermore, the synchronous illumination X-ray photoelectron spectroscopy and transient absorption spectroscopy were used to observe the photogenerated charge transfer path under light excitation, as well as density functional theory was used to calculate surface absorption energy, charge density distribution, and water oxidation kinetics. Combine the experimental and theoretical results to explain the mechanism of OEC surface active sites for enhancing photoelectrocatalytic performance. This project will provide experimental and theoretical basis for the study of solar photocatalytic and photoelectrocatalytic water splitting.