Efficient photocatalytic H2 evolution and Cr(VI) reduction under visible light using a novel Z-scheme SnIn4S8/CeO2 heterojunction photocatalysts

Semiconductor photocatalysis technology is a promising method for hydrogen production and water pollution treatment. Here, the SnIn4S8/CeO2 (SISC) composites were fabricated by a stirring and calcination method, and the mass ratio of SnIn4S8 to CeO2 was optimized. The 50 wt% SISC heterojunction photocatalyst has the highest visible light catalytic activity. The degradation rate of hexavalent chromium (Cr (VI)) is 98.8% in 75 min of light irradiation, which is 2.48 times that of pure CeO2. Besides, the 50 wt% SISC composite photocatalyst also has the highest photocatalytic hydrogen production efficiency (0.6193 mmol g-1 h-1), which exhibits a higher photocatalytic activity than pure CeO2 and SnIn4S8. The enhanced photocatalytic performance can be attributed to the Z-scheme heterojunction structure between CeO2 and SnIn4S8, which can effectively separate and transfer photogenerated charges, thereby reducing the recombination of photo-generated carriers. We hope this work can provide ideas for constructing Z-scheme heterojunction structures and improving photocatalytic activity under visible light.

Automated summary

The SnIn4S8/CeO2 (SISC) composites fabricated by a stirring and calcination method show promising photocatalytic activity under visible light, with good degradation effect on hexavalent chromium (Cr (VI)) and high hydrogen production efficiency.