A novel noble-metal-free Mo2C-In2S3 heterojunction photocatalyst with efficient charge separation for enhanced photocatalytic H2 evolution under visible light.

ABSTRACT

Currently, designing novel noble-metal-free photocatalysts with efficient carriers migration and catalytically active sites have been a researching hotspot in photocatalytic hydrogen evolution. In this paper, a novel noble-metal-free Mo2C-In2S3 heterojunction was synthesized by a simple hydrothermal method. Morphology characterization revealed In2S3 was attached to Mo2C. Electrochemical results showed Mo2C improved the interface conductivity, and promoted the transportation of photogenerated carriers. Under visible light, the optimal Mo2C-In2S3 composite achieved a H2 generation rate of 535.58 µmol h-1 g-1, which was 175.6 and 25.8 times higher than pristine In2S3 (3.05 µmol h-1 g-1) and In2S3-1% Pt (20.73 µmol h-1 g-1). In addition, a reasonable mechanism of the elevated photocatalytic activity was also discussed. This study demonstrates commercial Mo2C has an important effect of separating carriers and replacing Pt as co-catalyst in heterojunctions. This research also provides a method to design and synthesize new noble-metal-free photocatalysts for excellent hydrogen production activity.