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

[Display omitted] •2D metallic 1T-WS2 is distributed on g-C3N4 nanotubes to construct 1T-WS2/g-C3N4 composite.•The 1T-WS2/g-C3N4 composite is highly active for water splitting to produce hydrogen at 1021 μmol h−1 g−1.•1T-WS2 exhibits excellent electrical conductivity and offers abundant active sites on basal plane and edge sites.•The AQE of 1T-WS2/g-C3N4 composite achieves 11.23% under light at λ = 370 nm. 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 H2 production. The 1T-WS2/g-C3N4 composite with optimum 27% 1T-WS2 displays a significantly improved photocatalytic H2 production rate (1021 μmol 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 λ = 370 nm. Meanwhile, the 1T-WS2/g-C3N4 composites present an excellent photocatalytic H2 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 conductive 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.