Promoting charge separation of 0D/2D CsPbBr3/Bi2WO6 Z-scheme heterojunctions for boosting photocatalytic N2 reduction

Abstract

High efficient photocatalytic nitrogen fixation is an alternative strategy to solve the problems of energy consumption and environmental pollution of industrial ammonia production effectively, hence the selection and modification of catalysts are very important to improve the nitrogen fixation efficiency. In this article, a straightforward Z-scheme 0D/2D CsPbBr3/Bi2WO6 heterojunction was successfully constructed via a simple electrostatic self-assembly approach. By combining CsPbBr3 quantum dots (CPB QDs) with ultrathin Bi2WO6 (BWO) nanosheets, a large-area heterointerface of CPB QDs and BWO nanosheets was connected tightly thus shortened the charge transport distance effectively. This facilitates the efficient charge transfer between CPB and BWO through the Z-scheme interface, thereby achieving the purpose of promoting charge separation, which is well validated in differential charge. On the basis of various characterizations, the results indicated that the CPB/BWO heterojunction possessed an excellent photocatalytic nitrogen fixation performance: the production of NH3 at 3CPB/BWO heterojunctions (126.3 μmol‧g−1‧h−1) was about 17.1 times higher than that of pure CPB QDs. The new strategy may offer a new opportunity to the exploration and the research of halide perovskite-type photo catalysts with obviously enhanced nitrogen fixation activities.