MoS2/TiO2 heterostructures as nonmetal plasmonic photocatalysts for highly efficient hydrogen evolution

Abstract

In this study, we report nonmetal plasmonic MoS₂@TiO₂ heterostructures for highly efficient photocatalytic H₂ generation. Large area laminated MoS₂ in conjunction with TiO₂ nanocavity arrays is achieved via carefully controlled anodization, physical vapor deposition, and chemical vapor deposition processes. The broad spectral response ranging from ultraviolet-visible (UV-vis) to near-infrared (NIR) wavelengths and finite element frequency-domain simulations suggest that this MoS₂@TiO₂ heterostructure enhances photocatalytic activity for H⁺ reduction. A high H₂ yield rate of 181 μmol h⁻¹ cm⁻² (equal to 580 mmol h⁻¹ g⁻¹ based on the loading mass of MoS₂) is achieved using a low catalyst loading mass. The spatially uniform heterostructure, correlated with plasmon-resonance through the conformal MoS₂ coating that effectively regulates charge transfer pathways, is proven to be vitally important for the unique solar energy harvesting and photocatalytic H₂ production. As an innovative exploration, our study demonstrates that the photocatalytic activities of nonmetal, earth-abundant materials can be enhanced with plasmonic effects, which may serve as an excellent catalytic agent for solar energy conversion to chemical fuels.