Coupling SnS2 and rGO aerogel to CuS for enhanced light-assisted OER electrocatalysis

Abstract

In order to harvest more light wavelengths to improve the light-assisted electrochemical water splitting capacity, we developed a novel heterostructure of three-dimensional (3D) flower-like CuS architecture with accompanying SnS₂ nanoparticles and reduced graphene oxide (rGO) aerogel for outstanding light-assisted electrocatalytic OER performance and good stability. The excellent catalytic kinetics, effective capturing of visible light, and rapid charge transfer of the CuS/SnS₂/rGO (CSr) heterostructure were demonstrated. The overpotential (264 mV@10 mA cm⁻²) under light-assisted conditions is 20% lower than that under light-chopped conditions. SnS₂ can harvest more light wavelengths and this boosts its intrinsic activity. However, with the increase of the SnS₂ content, the OER activity decreases. The combination of the CS heterostructure and the rGO conductive aerogel achieves rapid charge transfer. Furthermore, the possible mechanism of the light-assisted electrocatalytic OER was also proposed. Overall, this work provides new insights into the simple and scalable fabrication of a highly efficient, low-cost, and stable non-noble-metal-based electrocatalyst.