The metallic 1T-phase WS2 nanosheets as cocatalysts for enhancing the photocatalytic hydrogen evolution of g-C3N4 nanotubes

Herein, we report that 2D metallic 1T-WS2 acts as co-catalyst in assisting g-C3N4 nanotubes (NTs) obtained via a simple grinding method for promoting photocatalytic H-2 production. The 1T-WS2/g-C3N4 composite with optimum 27% 1T-WS2 displays a significantly improved photocatalytic H-2 production rate (1021 mu mol h(-1) g(-1)), 17.6 times higher than g-C3N4 NTs. Besides, the apparent quantum efficiency (AQE) of 1T-WS2/g-C3N4 composite (27%) achieves 11.23% under light at lambda = 370 nm. Meanwhile, the 1T-WS2/g-C3N4 composites present an excellent photocatalytic H-2 production stability. The possible photocatalytic mechanism over 1T-WS2/g-C3N4 composites is proposed. Specifically, the photogenerated electrons from 1D g-C3N4 tubular nanostructure with open mesoporous morphology are migrated to conducive 1T-WS2 NSs quickly as electron acceptors along the 1D path. 1T-WS2 NSs can also offer abundant active sites on the edge and basal planes.