Photocatalytic H2 evolution on MoS2–TiO2 catalysts synthesized via mechanochemistry

Abstract

At present, composite photocatalysts containing MoS₂ as a co-catalyst and a subjective semiconductor material are usually obtained via various complex reduction methods using NH₄MoS₄ or Na₂MoO₄ as a precursor. In this work, a simple method was proposed to synthesize MoS₂–TiO₂ composite photocatalysts via mechanochemistry using MoS₂ as a direct precursor. 4.0% MoS₂–TiO₂ after ball-milling at 300 rpm for 2 h possessed the maximum photocatalytic activity for H₂ evolution. The rate of H₂ evolution was up to 150.7 μmol h⁻¹, which was 48.6 times higher than that of pure TiO₂. The MoS₂–TiO₂ composite possesses stable photocatalytic performance for H₂ evolution. Photoelectrochemical measurements confirmed the electronic interaction between TiO₂ and MoS₂. The photo-generated electrons on the conduction band of TiO₂ could easily transfer to the MoS₂ co-catalyst, which promoted efficient charge separation and improved the photocatalytic performance.