Construction of 2D/1D CuS nanosheets/MnCdS nanorods heterojunction for highly efficient photocatalytic hydrogen evolution.

Developing cost-effective cocatalyst-modified photocatalytic systems with boosted carrier separation and rapid surface catalytic reaction is an ideal strategy for effectively converting solar energy into desired fuels. Herein, a series of CuS/MnCdS hierarchical heterostructures are designed and fabricated to achieve efficient and robust photocatalytic H evolution by coupling one-dimensional (1D) MnCdS nanorods with two-dimensional (2D) CuS nanosheets through a facile sonochemical strategy. Benefiting from dimensionality and cocatalyst effects, the constructed 2D/1D CuS/MnCdS heterojunction photocatalyst containing 1.5 wt% CuS displays excellent photostability and superior photocatalytic H evolution rate up to 914.3 μmol h, which is 4.43 and 2.22-folds increment relative to bare MnCdS and the 3 wt% Pt/MnCdS, respectively. The various characterization results reveal that the utilization of semimetallic CuS nanosheets as the cocatalyst to form a Schottky heterojunction can promote the light-harvesting capability, suppress charge carrier recombination, and provide sufficient reaction sites for hydrogen generation, thereby resulting in the dramatically improved photocatalytic performance. This work clarifies the role of CuS nanosheets as the robust and cost-effective cocatalyst in the photocatalytic reaction and opens a new horizon for designing other CuS-based cocatalyst/semiconductor Schottky heterostructures for efficient solar-to-fuel conversion.