Ni3N/Co4N nanosheet heterojunction electrocatalyst for hydrogen evolution reaction in alkaline fresh water/simulated seawater

Abstract

Ni₃N/Co₄N nanosheet arrays on nickel foam were fabricated by using simple hydrothermal and nitriding two-step strategies. Their excellent performance is due to the synergistic effect between Ni₃N and Co₄N, the sufficient exposed active spots and the overall interaction of the three-dimensional cross-linking network formed by the nanosheet arrays and the porous nickel foam. Ni₃N/Co₄N exhibits high hydrogen evolution reaction activity. To yield a current density of 10 mA cm⁻², Ni₃N/Co₄N requires overpotentials of 58 and 85 mV in alkaline fresh water and simulated seawater, respectively. This work provides new understanding of developing feasible heterostructured electrocatalysts based on transition metal nitrides.