Interface engineering of N-doped Ni3S2/CoS2 heterostructures as efficient bifunctional catalysts for overall water splitting.

[Display omitted] • Heterostructure N-Ni 3 S 2 /CoS 2 catalyst was in situ growth on Ni foams. • The interconnected NiCo-LDH nanosheets were converted into continuous nanosheets after vulcanization. • N-Ni 3 S 2 /CoS 2 /NF catalyst exhibits excellent activity for both HER and OER. • N-Ni 3 S 2 /CoS 2 /NF delivers a cell voltage of 1.56 V in the water splitting reaction. • The catalytic performances are attributed to abundant interface and large electrochemical surface area. The design and synthesis of non-noble bifunctional electrocatalysts with high efficiency for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is still ongoing for enhanced overall water splitting. Herein, the heterostructure N-doped nickel sulfide/cobalt sulfide (N-Ni 3 S 2 /CoS 2) catalyst was in situ growth on Ni foams (NF) via an electrochemical deposition method followed by rapidly vulcanizing process at low-temperature. Benefiting from the abundant interface, high conductivity of NF, large electrochemical surface area, N-Ni 3 S 2 /CoS 2 /NF catalyst exhibits excellent activity for both HER and OER. Low overpotentials of 245 and 100 mV can drive a current density of 10 mA cm−2 for OER and HER in 1.0 M KOH. Serving as the bifunctional catalysts, N-Ni 3 S 2 /CoS 2 /NF catalyst delivers the current density of 10 mA cm−2 at a very low cell voltage of 1.56 V in the water splitting reaction. [ABSTRACT FROM AUTHOR]