Construction of defective Mo15S19/CdS-diethylenetriamine heterosctructure photocatalyst for highly active and stable noble-metal-free photocatalytic hydrogen production

Abstract

CdS, as semiconductor catalyst, has attracted much attention in photocatalytic production of hydrogen for the wide range utilization of visible light. Usually, noble metal deposited as a co-catalyst on CdS surface is required to achieve high photocatalytic activity. Thus, replacing noble metal via cheap and easy synthesis co-catalyst would be of great value for developing cost-effective photocatalyst. In this work, noble-metal-free defective Mo15S19 combined with CdS-diethylenetriamine (DETA) hybrid makes efficient separation of photoinduced carriers, and more importantly, reduced overpotential for hydrogen evolution reaction, thereby improved catalytic hydrogen evolution performance of designed composite. In particular, 3%Mo15S19/CdS-DETA systems exhibited a high rate of hydrogen production, reaching 3.61 mmol g−1 h−1, which is similar with 3%Pt/CdS-DETA and 9.5 and 2.19 times as high as that of CdS nanoparticles (NPs) and CdS-DETA, respectively. At the same time, photocorrosion resistance of 3%Mo15S19/CdS-DETA systems was dramatically improved. According to DFT theoretical calculations, it was found that the enhanced photocatalytic performance and anticorrosion are mainly due to efficient transfer of photoexcited electrons from CdS-DETA to Mo15S19.