Cooperative S-S coupling and H2 production from photocatalytic dehydrogenation of thiols over ReSe2/ZnIn2S4 heterostructure

Abstract

Photocatalytic anaerobic dehydrogenation provides a new avenue to cooperatively produce clean fuels and fine chemicals, while minimizing waste discharge and reducing environmental impact. Here, we demonstrate an efficient co-production of disulfides and H2 via photocatalytic S-S dehydrogenation of thiols using a two-dimensional (2D) heterostructure of ultrathin ZnIn2S4 (ZIS) nanosheets decorated with dispersed (1T phase) ReSe2 nanoparticles. Experimental characterizations and DFT calculations reveal that integrating ReSe2 with ZIS leads to the formation of a robust internal electric field (IEF) within the ReSe2/ZIS heterostructure. The distorted 1T phase ReSe2 with abundant active Se sites and a high Fermi level induces downward band bending of ZIS at the interface, which promotes charge separation and expedites H2 evolution. Moreover, the introduction of ReSe2 provides more adsorptive sites, increasing the concentration of reactants on the catalyst surface. This enhancement fosters surface interactions between the catalyst and p-toluenethiol (PTT), ultimately accelerating the reaction rate. The optimal H2 and S-S coupling p-tolyl disulfide (PTD) production rates of the 5 wt% ReSe2/ZIS composite reach 2275 and 2303 µmol g−1h−1, respectively, approximately 5 times greater than those of blank ZIS. Importantly, the selectivity of PTD reaches 98.4 %. This visible-light-driven dehydrogenation process aligns with the principles and objectives of green chemistry, realizing high atom economy without generating byproducts. It is anticipated to open new possibilities for sustainable and environmentally friendly routes for synthesizing high-value chemicals and producing clean energy.