Self-standing 2D tin-sulfide-based heterostructured nanosheets: An efficient overall urea oxidation catalyst

Abstract

In this work, SnS/SnS2 heterostructured film on a nickel foam (NF) through solution process was grown and employed directly as cathode and anode to the urea oxidation reaction (UOR). The as-fabricated SnS/SnS2 film achieves high efficiency toward UOR with a lower potential of 1.38 V vs RHE to deliver 50 mA cm(-2), which is approximately 200 mV less than the potential demanded for the oxygen evolution reaction (OER). More importantly, the electrolyzer consisting of two identical electrodes with the SnS/SnS2/NF || SnS/SnS2/NF vs RHE assembly oxidizes urea at a lower potential of 1.36, 1.38, and 1.39 V vs RHE to deliver a current density of 10, 50, and 100 mAcm(-2), respectively. The superior UOR performance of the SnS/SnS2-based electrode is attributed to the combined merits of the SnS and SnS2 phases in the heterostructure, enhancing the catalytic active sites and providing the easy charge transport between the electrode and electrolyte.