Titanium carbide MXenes coupled with cadmium sulfide nanosheets as two-dimensional/two-dimensional heterostructures for photocatalytic hydrogen production

Two-dimensional (2D)/2D heterostructures with close contact are believed to be important for photo-catalysis owing to a 2D ultrathin structure, a large surface area, and an efficient carrier separation or transfer. In this study, we designed and prepared a unique 2D/2D cadmium sulfide (CdS) nanosheet (NS)@titanium carbide (Ti3C2) MXene composite photocatalyst. The results show that the CdS NSs can be controllably assembled on conductive Ti3C2 MXene via a one-step hydrothermal strategy. The 2D/2D CdS NS@Ti3C2 MXene composites with 5 mg of Ti3C2 MXene show a higher photocatalytic perfor-mance (1.73 mmol h(-1) g(-1)) than pure CdS NSs (0.37 mmol h(-1) g(-1)) and CdS NS@Ti3C2 MXene composites with other MXene contents (3 mg, 7 mg, 10 mg, and 20 mg). The improved photocatalytic activity can be attributed to the high surface area as confirmed by a BET analysis and enhanced charge separation activity between CdS and Ti3C2 MXene. (C) 2022 Elsevier Inc. All rights reserved.

Automated summary

Two-dimensional (2D)/2D heterostructures with close contact are important for photo-catalysis due to their ultrathin structure, large surface area, and efficient carrier separation or transfer. In this study, a unique 2D/2D CdS NS@Ti3C2 MXene composite photocatalyst was designed and prepared, showing improved photocatalytic performance. The enhanced activity can be attributed to the larger surface area and enhanced charge separation activity between CdS and Ti3C2 MXene.