Facile synthesis of MoS2/B-TiO2 nanosheets with exposed {001} facets and enhanced visible-light-driven photocatalytic H2 production activity

Abstract

Cocatalysts have been extensively used to accelerate the rate of hydrogen evolution in semiconductor-based photocatalytic systems; however, the influence of interface states between the semiconductor and cocatalyst has rarely been investigated. Herein, we demonstrated a feasible strategy of heterogeneous structure to enhance visible light hydrogen generation of the MoS₂/B-TiO₂ system. Loading of MoS₂ nanosheets on the surface of anatase boron doped TiO₂ (B-TiO₂) nanosheets with exposed {001} facets considerably increases the interfacial contact. At an optimal ratio of 1.0 wt% MoS₂, the MoS₂/B-TiO₂ hybrid photocatalyst showed the highest H₂ evolution rate of 0.50 mmol h⁻¹ g⁻¹, which is almost 6 times higher than that of pure B-TiO₂ nanosheets. More importantly, the MoS₂/B-TiO₂ hybrid photocatalyst exhibited photocatalytic activity much higher than that of Pt/B-TiO₂ nanosheets and the simple mechanical mixing of B-TiO₂ and MoS₂ nanosheets photocatalysts. The decisive factor in improving the photocatalytic H₂ production activity is an intimate and large contact interface between the light-harvesting semiconductor and cocatalyst. The effective charge transfers from B-TiO₂ to MoS₂ was demonstrated by the significant enhancement of the photocurrent responses in MoS₂/B-TiO₂ hybrid electrodes. This study created new opportunities for designing and constructing highly efficient visible light photocatalysts by surface modification or doping.