Nanostructured Co3O4@NiFe-LDH heterojunction catalysts for improving oxygen evolution reaction in alkaline environment

Abstract

Constructing nano-heterojunction catalysts is a highly efficient method for enhancing the thermodynamics and kinetics towards oxygen evolution reaction. In the present study, NiFe-LDH nanoparticles in-situ grown on Co3O4 nanowires bring about abundant heterogeneous interfaces, which productively increase specific surface area and tune electron density distribution. The as-obtained composite comprises rich unsaturated Co sites on Co3O4 and hybrid crystalline/amorphous NiFe-LDH phase, both of which expedite the flow of charge and expose large amounts of active sites. The Co-Ni-Fe electron transport channels are established at the core-shell heterojunction with the transmission of electrons from Co3O4 to NiFe-LDH. The resultant optimal Co3O4 @NiFe-LDH/NF-100 catalyst displayed attractive OER activity with low overpotential of 270 mV at 50 mA cm−2, along with excellent durability in alkaline media. This typical core-shell heterojunction promotes H2O dissociation and strengthens the adsorption of intermediates, thereby enhancing oxygen evolution reaction.