In situ growth Fe and V co-doped Ni3S2 for efficient oxygen evolution reaction at large current densities

Abstract

Industrial electrolysis of water is one of the effective strategies for green hydrogen production in the future. Nevertheless, the large-scale applications of water electrolysis are still intractable issues hindered by the high overpotentials and inferior reaction kinetics on the anode. Herein, a facile one-step hydrothermal method was applied to in situ growth the Fe and V co-doped Ni 3 S 2 electrocatalyst on nickel foam substrate (Fe, V–Ni 3 S 2 /NF). In 1 M KOH electrolyte, the as-prepared Fe, V–Ni 3 S 2 /NF electrode exhibited an improved water oxidation activity with ultralow overpotentials of 253 and 370 mV to realize large current densities of 100 and 1000 mA/cm 2 , respectively. More importantly, the Fe, V–Ni 3 S 2 /NF electrode existed an activation process during 100 h chronopotentiometry testing period. Detailed characterizations revealed that elements of V and S in the electrocatalyst were oxidized and dissolved into the electrolyte, making the electrocatalyst undergo surface reconstruction and resulting in a faster kinetic reaction rate, thus leading to enhanced oxygen evolution reaction activities. Collectively, the resultant Fe, V–Ni 3 S 2 /NF in this work provides new cogitation towards design and synthesis of low-cost electrocatalyst with large current densities for water oxidation. • Fe,V–Ni 3 S 2 /NF electrode was hydrothermal prepared and used as OER electrocatalyst. • Ni 3 S 2 is converted to NiOOH during the electrochemical oxidation process. • The electrode can attain 100 and 1000 mA/cm 2 with overpotentials of 253 and 370 mV. • The enhanced OER activity owned to the surface reconstruction by V, S etching.