Photocatalytic water splitting on BiVO4: Balanced charge-carrier consumption and selective redox reaction
Xiangjiu Guan, Li Tian, Yazhou Zhang, Jinwen Shi, Shaohua Shen
Abstract
Surficial redox reactions play an essential role in photocatalytic water splitting, and are closely related to the surface properties of a specific photocatalyst. In this work, using monoclinic BiVO4 decahedral single crystals as a model photocatalyst, we report on the interrelationship between the photocatalytic activity and the surficial reaction sites for charge-carrier consumption. By controlled hydrothermal synthesis, the ratio of {010} to {110} facets on BiVO4, which respectively serve as reductive and oxidative sites, is carefully tailored. Our results show that superior photocatalytic water oxidation could be obtained on BiVO4 decahedrons with a medium ratio of reductive/oxidative sites and that efficient overall water splitting could be achieved via further modification of appropriate cocatalysts in Z-scheme system. The excellent photocatalytic performance is attributed to the accelerated selective redox reactions by realizing balanced charge-carrier consumption, which provides insightful guidance for prospering photocatalytic reactions in energy conversion.