Construction of Heterogenous S–C–S MoS2/SnS2/r-GO Heterojunction for Efficient CO2 Photoreduction

Photocatalytic reduction of CO2 by semiconductors is of great significance in generating value-added fuels. Here, we construct a novel S–C–S heterojunction constituted of MoS2/SnS2/r-GO by a simple solvothermal method. The prepared MoS2/SnS2/r-GO showed significant photoexcitation of photosensitive oxygen (ROS) by electron spin resonance spectroscopy, demonstrating that superoxide radicals (•O2–), pores, and hydroxyl radicals (•OH) are the main active species. The constructed S–C–S heterojunction has a multilevel electron transport mechanism and synergistic effect, which provides the possibility of producing more organic fuel. The photocatalytic materials were characterized by XRD, XPS, SEM, TEM, PL, etc. As a result, the atomic layer MoS2/SnS2/r-GO heterojunction exhibited a CO formation rate of 68.53 μmol g–1 h–1 and a CH4 formation rate of 50.55 μmol g–1 h–1, respectively. This work opens up new prospects for the formation of heterojunctions of chalcogenide transition-metal sulfides.