Abstract
? 2022 Elsevier B.V.Good interfacial compatibility is essential to grow intermetallic compound layer on the surface of substrates for the potential application of electrocatalytic reactions. Here, an interface strategy is proposed to prepare a free-standing copper-cobalt-nickel nitride electrode，in which copper-cobalt-nickel nitride is anchored on hydrophilic treated nickel foam. Compared to bi-metal hierarchical catalysts, the as-fabricated epitaxial heterostructure shows excellent oxygen evolution reaction (OER) activity with an ultralow overpotential of 190 mV, as well as an overpotential of 63 mV for hydrogen evolution reaction (HER) at the current density of 10 mA cm–2. Most importantly, the modified tri-metal nitrides exhibit improved interfacial compatibility due to the interfacial defects, which can increase electron transport across the junction during the catalytic reactions. Density functional theory calculations reveal that the synergistic effect between copper, cobalt, and nickel nitride creates a proper electronic structure that lowers the reaction barriers of HER/OER.
NSTL
Elsevier