Development of CuN electrocatalyst for hydrogen evolution reaction in alkaline medium.

A wide variety of electrocatalysts has been evolved for hydrogen evolution reaction (HER) and it is reasonable to carry out HER with low cost electrocatalyst and a good efficiency. In this study, CuN was synthesized by nitridation of CuO and further utilized as an electrocatalyst towards HER. The developed CuN electrocatalyst was tested and results showed a low overpotential and moderate Tafel slope value (overpotential: 149.18 mV and Tafel slope 63.28 mV/dec at 10 mA/cm) in alkaline medium with a charge transfer resistance value as calculated from electrochemical impendence spectroscopy being 1.44 Ω. Further from the experimental results, it was observed that the reaction kinetics was governed by Volmer-Heyrovsky mechanism. Moreover, CuN has shown an improved rate of electron transfer and enhanced accessible active sites, due to its structural properties and electrical conductivity. Thus the overall results show an excellent electrochemical performance, leading to a new pathway for the synthesis of low cost electrocatalyst for energy conversion and storage.