Self-supported nickel nitride as an efficient high-performance three-dimensional cathode for the alkaline hydrogen evolution reaction

Transition metal nitrides (TMNs) attract a lot of attention due to their excellent catalytic activities for energy related applications, although TMN catalysts developed as HER catalysts in alkaline environment are limited. Herein, we report a very simple and straightforward method to fabricate self-supported nickel nitride film on nickel foam (Ni3N/NF) via direct nitridation of NF under NH3 atmosphere. The Ni3N/NF, as an efficient 3D hydrogen-evolving cathode, needs overpotentials of 121, 177, and 254 mV to attain current densities of 10, 20, and 100 mA cm−2, respectively, and it maintains its catalytic activity for at least 32 h in alkaline media. Additionally, this electrode is also highly efficient under neutral and acidic conditions. The scalable fabrication approach reported here can be extended to synthesize other self-supported transition metal nitride HER cathodes.