Iron and vanadium co-doped Ni3S2 flower like nanosheets as an efficient electrocatalysts for water splitting

Abstract

For the production of sustainable hydrogen energy from water electrolysis, it is now essential to create an efficient bifunctional electrocatalysts for OER and HER (oxygen and hydrogen evolution reaction). We have synthesized a bi-metallic heterogeneous electrocatalyst of iron and vanadium codoped nickel sulphide (FeV-Ni3S2) flower like nanosheets self-supported on conductive nickel foam (NF) substrate by a typical hydrothermal method. Herein, our investigation is focused on achieving an efficient electrocatalytic performance and long-term stability (> 48 h) in an alkaline environment (1 M KOH). The results of FeV-Ni3S2/NF exhibits an outstanding electrochemical performance with lower overpotentials of 149 mV for HER and 183 mV for OER at 10 mA cm−2, and a lower cell voltage of 1.56 V, respectively. The lattice distortion in Ni3S2 caused by FeV-doping, and the enrichment of sulphur active edge sites contributes to the improved electrochemical performance of FeV-Ni3S2/NF. Moreover, the interconnected flower like nanosheets increasese the conductivity, density of active sites and electrochemical surface area to facilitate the mass transport of reactants, benefiting stable water electrolysis for efficient hydrogen production. This work will provide novel insights into the design of bi-metal-doped materials for energy conversion and storage applications.