Highly efficient electrocatalyst of single metal atom doped 2D WS2 for ORR and OER

Abstract

Abstract To search for efficient electrocatalyst towards ORR and OER for sustainable energy conversion, storage, and utilization, a family of single transition-metal atom (Mn, Fe, Co, Ni, Cu and Zn) doped two-dimensional tungsten disulfide monolayers have been systematically investigated by using first-principle computations to uncover the impact of transition-metal dopants on ORR and OER electrocatalytic activities. It is demonstrated that single-metal-atom sites can bind to the surface of 2D WS2, enhancing the adsorption of intermediates involved in the OER/ORR and decreasing overpotentials effectively. Compared to the pristine 2D WS2, most of transition-metal doped catalysts can decrease overpotentials and promote OER and ORR activities effectively. Particularly, Ni@WS2 and Zn@WS2 are screened out to exhibit the best electrocatalytic activity among all systems with an overpotential of 0.33 and 0.47 V for OER process, respectively, showing that Ni@WS2 and Zn@WS2 are potential candidates for OER electrocatalysts. Furthermore, their electrocatalytic performance are explained in terms of volcano plot, scaling diagram, d-band center model, and charge analysis.