Solvothermal decoration of Cu 3 SnS 4 on reduced graphene oxide for enhanced electrocatalytic hydrogen evolution reaction

Metal sulphides combined with graphene/reduced graphene oxide (rGO) represent a unique class of materials for hydrogen generation either through electrocatalytic or photo(electro) catalytic methods. Herein, we report a solvothermal synthesis of Cu 3 SnS 4 decorated rGO resulting in a highly active electrocatalyst for hydrogen evolution reaction (HER) compared to its native Cu 3 SnS 4 . The Cu 3 SnS 4 ‐rGO exhibited very low overpotential of 190 mV versus reversible hydrogen electrode (RHE), whereas Cu 3 SnS 4 requires 250 mV versus RHE at a current density of 10 mA/cm 2 . Tafel slope of Cu 3 SnS 4 ‐rGO and Cu 3 SnS 4 is about 64 and 76 mV/dec, respectively. This suggests that Cu 3 SnS 4 ‐rGO is a better electrocatalyst when compared to Cu 3 SnS 4 and follows mixed Volmer and Heyrovsky mechanism for HER.