Fe-V synergistic doping effect of hierarchical Ni3S2 oblate-nanorod arrays for efficient electrocatalytic oxygen evolution reaction

• Fe-V co-doping Ni 3 S 2 oblate-nanorod arrays were fabricated by one-step hydrothermal process. • The obtained electrocatalyst exhibits outstanding OER catalytic performance and stability. • The Fe-V co-doping improves the intrinsic activity and accelerates the kinetics of the reaction. • The introduction of Fe and V elements could tune the morphology and optimize electronic structure. It is an urgent challenge to develop low-cost and high-performance catalysts for the oxygen evolution reaction (OER). Herein, Fe-V co-doping Ni 3 S 2 -based oblate-nanorod arrays electrocatalysts supported by nickel foam (FV-Ni 3 S 2 /NF) have been successfully synthesized through hydrothermal technique. An increase in electrochemically active surface area and a decrease in charge-transfer resistance by the synergistic incorporation of Fe and V as well as the presence of α-Ni(OH) 2 and γ-FeOOH on the surface of the catalysts effectively accelerate the OER kinetic process, and display an enhanced OER activity and stability in the alkaline media, resulting in a considerable improved overpotential of 259 mV at 100 mA cm −2 and a Tafel slope of 22.38 mV dec −1 , far superior to pure NF, Ni 3 S 2 /NF, V-Ni 3 S 2 /NF, Fe-Ni 3 S 2 /NF and IrO 2 . Furthermore, i-t stability test after 50 h of FV-Ni 3 S 2 /NF indicates that the current density drop ratio is only 1.3%, exhibiting excellent electrocatalytic stability. Thus, our studies provide a new strategy of designing cost-effective and high-performance catalysts through the introduction of double heteroatoms and interface/surface synergistic regulating engineering.