The metallic 1 T-WS2 as cocatalysts for promoting photocatalytic N2 fixation performance of Bi5O7Br nanosheets

Abstract Recently, widespread attention has been devoted to the typical layered BiOCl or BiOBr because of the suitable nanostructure and band structure. However, owing to the fast carrier recombination, the photocatalytic performance of BiOX materials is not so satisfactory. Loading 1 T phase WS2 nanosheets (NSs) onto Bi5O7Br NSs can improve the photocatalytic N2 fixation activity. Among these, the obtained 1 T-WS2@Bi5O7Br composites with optimum 5% 1 T-WS2 NSs display a significantly improved photocatalytic N2 fixation rate (8.43 mmol L-1 h-1 g-1), 2.51 times higher than pure Bi5O7Br (3.36 mmol L-1 h-1 g-1). And the outstanding stability of 1 T-WS2@Bi5O7Br-5 composites is also achieved. Exactly, the photoexcited electrons from Bi5O7Br NSs are quickly transferred to conductive 1 T phase WS2 as electron acceptors, which can promote the separation of carriers. In addition, 1 T-WS2 NSs can provide abundant active sites on the basal and edge planes, which can promote the efficiency of photocatalytic N2 fixation. This work offers a novel solution to improve the photocatalytic performance of Bi5O7Br NSs.