Design and in-situ synthesis of unique catalyst via embedding graphene oxide shell membrane in NiS2 for efficient hydrogen evolution

•Graphene oxide encapsulating NiS2 electrocatalyst was fabricated by a scalable and facile method.•The liquid precursor benefits surface/interface engineering and formation of tightly coupled interface.•The catalyst exhibits highly enhanced HER and OER catalytic activity and durability.•Excellent performance contributes to its unique architecture and coupled interface.