One-step synthesis of two dimensional Bi2VxW1−xO6−δ solid solution for photocatalytic hydrogen evolution

Photocatalytic H 2 evolution through water splitting on the semiconductor catalysts is a promising and efficient solution to convert inexhaustible solar energy into chemical fuel. In this report, the robust two-dimensional BWV-x (0 ≤ x ≤ 0.5) solid solution were synthesized via a facile one-step strategy for photocatalytic H 2 evolution. The band gaps of BWV-x could be tuned easily in a wide range from 3.0 to 2.2 eV according to their chemical composition. When the value of x was 0.33, the BWV-0.33 displayed a high H 2 generation rate of 747 μmol.h −1  g cat −1 , which was about 5.2-fold that of pristine Bi 2 WO 6 . Mott-Schottky and UV–Vis absorbance spectroscopy studies of BWV-x revealed that the appropriate band gap and high conduction band edge position of BWV-0.33 led to a significant improvement in photocatalytic performance. The charge transfer mechanism for H 2 production over the BWV-0.33 was further proposed. This work shows the potential of band gap engineering by constructing solid solutions for efficient semiconductor photocatalysis.