Facet-selective charge separation in two-dimensional bismuth-based photocatalysts

Abstract

Facet-selective charge separation in semiconductors has been considered one of the most vital factors to improve their photocatalytic performance and selectivity, which is ascribed to the suppressed charge recombination and separated redox active sites among facets. In this review, we summarize the recent advances in the facet design of two-dimensional bismuth-based semiconductors, which is mainly based on the facet-dependent charge carrier migration to expose the relevant active crystal facets for specific photocatalytic reactions. The review starts with some typical bismuth-based single-crystal plates, and the control of their specific exposed facets is introduced. We then discuss the facet-dependent charge separation and photocatalytic applications of bismuth-based single-crystal plates, in which the highly exposed facets and co-exposed facets are summarized. In particular, pH regulation and introduction of piezoelectric or ferroelectric polarization, emerging as promising and efficient strategies for manipulating the facet-selective charge separation in photocatalysts, are highlighted. Finally, future prospects for developing high-performance photocatalysts with efficient charge separation and surface reaction kinetics are proposed.