Accelerated electrocatalytic hydrogen evolution on non-noble metal containing trinickel nitride by introduction of vanadium nitride

Trinickel nitride as a kind of promising hydrogen evolution reaction (HER) electrocatalyst has attracted much attention in recent years due to its high electrical conductivity and low cost. Herein, we designed and synthesized a novel and efficient Ni3N@VN-NF composite by nitriding treatment of a NiV-LDH precursor. The obtained electrode exhibits superior performances including a much lower overpotential of 56 mV at 10 mA cm(-2) and Tafel value of 47 mV dec(-1) compared to pure Ni3N-NF and VN-NF electrodes. The Ni3N@VN-NF composite as a cathode and a conventional OER electrode NiFe-LDH-NF as an anode were combined to form a complete water-splitting system. The voltage at 10 mA cm(-2) is about 1.55 V, which is superior to the voltage value reported in many literature studies. In addition, the two-electrode system exhibits excellent durability after as long as 50 hours of operation.