Enhanced photocatalytic water oxidation by hierarchical 2D-Bi2MoO6@2D-MXene Schottky junction nanohybrid

Abstract Developing stable photocatalysts with high-efficiency water oxidation is crucial for photocatalytic water splitting. Herein, Bi2MoO6 nanosheets are grown in-situ onto the surface of MXene (Ti3C2TX) nanosheets to obtain hierarchical 2D-Bi2MoO6@2D-MXene nanohybrid. The design and construction of the nanohybrid not only suppress the agglomeration of Bi2MoO6 nanosheets, but also improve the specific surface area to maximize the exposed activity sites of Bi2MoO6 nanosheets. The Schottky heterojunction, derived from the introduction of MXene nanosheets, could simultaneously boost photoinduced electron transport and limit photoexcited electron-hole recombination. As a result, the optimized nanohybrid exhibits enhanced visible-light photocatalytic water oxidation activity of 734.0 μmol h−1 g−1 (7.9 times higher than that of pristine Bi2MoO6), more photogenerated free radicals ( OH and O2−) and excellent stability (16 h of cycle experiments). This work shows that the MXene-based Schottky heterojunction is a promising system for photocatalytic water splitting applications.