Heterostructured FeSe2-CoSe2 Nanorods Supported on Nitrogen and Sulfur co-doped Reduced Graphene Oxide as High‐Performance Electrocatalyst for Oxygen Evolution Reaction

Abstract

With the aim of hydrogen production from electrochemical water splitting on a high scale, the core challenge is to develop an effective oxygen evolution reaction (OER) electrocatalyst with high activity as well as a low cost. Herein, we developed a heterostructure of Iron and cobalt selenide supported by a dual heteroatom (Nitrogen and Sulphur) doped reduced graphene oxide, synthesized by an easy solvothermal method. The as-synthesized CoSe2-based catalyst consists of urchin-like assembled nanorods resulting in the highly exposed reaction sites and shows excellent electrochemical performance with the much lowest overpotentials of 216 mV and 291 mV at a current density of 10 and 50 mA cm−2, respectively, Tafel slope of 53.4 mV dec−1 and long-term stability for 50 h in an alkaline environment. As a result, the improved OER activity of the as-synthesized electrocatalyst could be attributed to the highly accessible heterointerfaces served as abundant catalytic active sites as well as strong synergistic interaction and enhanced electrical conductivity that increased the movement of electron transfer. The achieved results manifest the superiority of the prepared electrocatalyst towards OER and it can be a remarkable electrocatalyst which is helpful for further development in the practical application of water splitting to decrease energy utilization at a high scale.