Synthesis of Synergistic Nitrogen-Doped NiMoO₄/Ni₃N Heterostructure for Implementation of an Efficient Alkaline Electrocatalytic Hydrogen Evolution Reaction

Electrochemical water splitting is considered as an effective and promising method to produce the ideal hydrogen energy to solve the energy crisis and environmental pollution problems. Herein, we successfully synthesized the N-doped NiMoO4/Ni3N heterostructure, which exhibited an efficient HER performance with a lower overpotential of 51 mV at 10 mA cm–2 and a lower Tafel slope value of 45.47 mV dec–1 compared with those of NiMoO4, N-doped NiMoO4, or Ni3N owing to the synergistic effect of N doping and construction of the superior heterostructure. When the N-doped NiMoO4/Ni3N heterostructure is used as a cathode and the well-recognized excellent OER material (NiFe-LDH) is used as an anode to construct the two-electrode electrolyzer, the system requires only 1.506 and 1.559 V to achieve the current densities of 10 and 20 mA cm–2, respectively, which are lower than those of the commercial Pt/C//RuO2 system (1.573 and 1.634 V, respectively) or many other reported systems. At the same time, this two-electrode system demonstrates excellent durability in electrocatalytic water splitting. This design method paved the way for the development of another electrocatalytic system.