Tuning the morphologic and electronic structures of self-assembled NiSe/Ni3Se2 heterostructures with vanadium doping toward efficient electrocatalytic hydrogen production

Tailoring the nonprecious nickel selenide heterogeneous electrocatalysts with controllable morphology and electronic structures is of prime importance to enhance the catalytic efficiency for hydrogen production evolution (HER). Here, we report the solvothermal in-situ synthesis of vanadium-incorporated NiSe/Ni3Se2 heterogeneous structures (VNS) on porous nickel foam, which function as an efficient electrode toward HER, together with superior catalytic activity and durability. Impressively, the self-assembled VNS electrode delivers the current densities of 100, 500 and 1000 mA cm−2 at quite low overpotentials of 175, 275 and 348 mV with 85% iR-compensation toward HER in 1.0 M KOH solution. Mott-Schottky analysis indicates that the vanadium doping alters the flat band potential of VNS, and in turn affects the electrons migration behavior at electrode and electrolyte interface. Benefiting from its dramatically increased catalytic active sites exposure, enhanced charge transport capability, and optimized electronic structure, the hierarchical VNS heterostructures exhibit an impressive HER electrocatalytic performance in alkaline media. More broadly, this research provides a promising strategy for design and exploitation of more advanced electrocatalysts for large-scale hydrogen production on selenides using heteroatom vanadium incorporation.