Accelerating Interfacial Charge Transfer in CrC/MnCdS Schottky Junction for Photothermal-Enhanced Photocatalytic H2 Production

Abstract

Construction of Schottky junction with photothermal enhancement offers an effective strategy to mitigate the rapid recombination of charge carriers and enhance interfacial charge transfer efficiency during photocatalytic hydrogen evolution. In this work, a CrC/MnCdS Schottky junction photocatalyst was successfully constructed through the physical incorporation of metal-like CrC nanoparticles and 1D MnCdS nanorods. Density functional theory (DFT) calculations reveal the metal-like nature of CrC, enabling the formation of a Schottky junction with MnCdS that generates a strong internal electric field (IEF), which greatly facilitates the spatial separation and migration of photogenerated charge carriers. CrC possesses broad-spectrum light absorption capability and photothermal effect, which enhance the light absorption ability of the composite and increase the local reaction temperature, thereby lowering the hydrogen desorption barrier, and accelerates reaction kinetics. Consequently, the optimized 20%CrC/MnCdS photocatalyst exhibits a superior H2 evolution rate of 2.61 mmol h–1 g–1, which is approximately 2.96 times higher than that of pure MnCdS. The improved photocatalytic activity arises from the synergy between the Schottky junction and the photothermal effect, which markedly improves the charge separation and concurrently accelerates the interfacial reaction kinetics. This work offers a viable approach for constructing high-efficiency photothermally-assisted photocatalytic systems.