Spherical V-doped nickel-iron LDH decorated on NiS as a high-efficiency electrocatalyst for the oxygen evolution reaction.

Due to the slow reaction kinetics of the oxygen evolution reaction (OER), the electrolysis rate of water is greatly limited. Therefore, it is of great significance to study stable and efficient non-noble metal based electrocatalysts. In this paper, three-dimensional (3D) spherical V-NiFe LDH@NiS was developed by exquisitely decorating ultra-thin V-doped NiFe layered dihydroxide (NiFe-LDH) on NiS nanosheets supported by nickel foam (NF). It is worth mentioning that V-NiFe LDH@NiS exhibits an excellent electrocatalytic performance and only 178 mV overpotential is required in 1 M KOH to achieve a current density of 10 mA cm. Long-term chronoamperometry manifests its superior electrochemical stability. The combination of NiFe LDH and conductive substrate coupling can drastically afford abundant active sites and accelerate charge transfer, and V doping can markedly regulate the electronic structure. Therefore, the activity and durability of the electrocatalysts are greatly improved. This study may provide a new strategy for the preparation of efficient OER electrocatalysts.