Interface engineering of bimetallic nitrides nanowires as a highly efficient bifunctional electrocatalyst for water splitting

Electrolytic water splitting offers a prodigious amount of hydrogen and oxygen production, which could satisfy the demand for clean energy for building the community of human destiny. Thus, as the key technology barrier, the development of a low-cost and high-performance bifunctional transition metal electrocatalyst toward water splitting is still a challenge. In this work, aiming to enhance electrocatalytic performance, the nickel molybdenum nitride heterostructure nanowire arrays were synthesized on nickel foam (Ni 3 N-Mo 2 N/NF) via hydrothermal strategy followed by a direct nitridation, from which the heterostructure nanowire was achieved. The self-supporting Ni 3 N-Mo 2 N/NF electrodes exhibits very low overpotentials of 66 and 252 mV at 10 mA cm −2 for the hydrogen evolution reaction and oxygen evolution reaction, respectively. When the cathode and anode were both Ni 3 N-Mo 2 N/NF, a current density of 10 mA cm −2 was achieved with only 1.55 V. This work provides a new idea for the design and preparation of non-precious metal-based transition metal nitride catalysts. • Nickel molybdenum nitride heterostructure arrays was designed as efficient bifunctional electrocatalysts. • The Ni 3 N-Mo 2 N/NF catalyst only needs a cell voltage of 1.55 V to drive 10 mA cm −2 . • Catalytic performance is enhanced by optimization of heterostructure interfaces.