Strained heterointerfaces in sandwich–like NiFe layered double hydroxides/Co1-xS for highly efficient and superior long–term durable oxygen evolution reaction

•Sandwich–like NiFe LDH/Co1-xS heterostructure has been successfully prepared.•The 3D catalytic space provides extra active sites over the original NiFe LDH.•The lattice mismatch of NiFe LDH induces the formation of lattice strain in Co1-xS.•The compressive strain possesses lower free energy in OER.•NiFe LDH/Co1-xS exhibits excellent long–term durability after 150 h test.