Dual functional Z-scheme ReS2/CdIn2S4 catalyst efficiently photocatalyzes H2O2 production and CO2 reduction in pure water without sacrificial agents

Photocatalytic production of hydrogen peroxide (H 2 O 2 ) and carbon dioxide (CO 2 ) reduction has been the hotspots in the field of chemical industry for a long time. CdIn 2 S 4 is widely used due to its excellent thermal stability and significant absorption in the visible light region. However, the low efficiency of photogenerated charge separation hinders its practical application. In this work, Z-scheme heterojunction ReS 2 /CdIn 2 S 4 was successfully synthesized by hydrothermal method and applied for the first time in photocatalytic production of H 2 O 2 and CO 2 reduction. The experimental results show that compared with pure CdIn 2 S 4 or pure ReS 2 , the photocatalytic performance of ReS 2 /CdIn 2 S 4 is greatly improved. When the loading amount of ReS 2 is 12 wt. % of CdIn 2 S 4 , it exhibits the optimal photocatalytic H 2 O 2 productivity of 361.8 μmol h -1 g -1 and the optimal yields of CO and CH 4 of 89.84 and 5.03 μmol h -1 g -1 respectively in pure water. The Z-scheme heterojunction of ReS 2 /CdIn 2 S 4 was determined by XPS and the band structure. In addition, two possible reaction pathways involving O 2 - and 1 O 2 were analyzed for the H 2 O 2 production by RS/CIS and the pathway of carbon dioxide reduction reaction can be speculated through in-situ DRIFTS.