Coral-like-Structured Ni/C₃N₄ Composite Coating: An Active Electrocatalyst for Hydrogen Evolution Reaction in Alkaline Solution

Abstract

Exploiting high-efficiency catalysts toward hydrogen evolution reaction (HER) is a significant assignment nowadays. We find a quick and straightforward means to produce large-scale g-C3N4, which does not use template and easily obtains uniform nanostructures. And, we fabricate one-step preparation of a non-noble-metal catalyst, consisting of carbon material and transition metal only, by coupling graphitic carbon nitride (g-C3N4) with Ni. The results show that Ni/C3N4 composite catalyst possesses coral-like structure and its unique morphology is in favor of electrochemical activity for HER. Simultaneously, the Ni/C3N4 composite catalyst presented prominent activity on HER with a high exchange current density of 1.91 × 10–4 A cm–2, a low Tafel slope of 128 mV dec–1 and small overpotentials of 356 and 222 mV to reach current densities of 100 and 10 mA cm–2, which are superior to those of the state-of-the-art HER-active Ni-based compositions, as well as majority other metal-free catalysts, and even rivaled the electrocatalytic property of commercial Pt/C catalyst.