Interfacial engineering of CuCoLDH@GDY/NF heterostructure for bifunctional electrocatalysis in alkaline water splitting: Mechanistic insights and scalable synthesis

Abstract

The development of low-cost and highly efficient dual-functional catalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) poses a significant challenge in the field of electrochemical overall water splitting research. In this study, granular copper cobalt layered double hydroxide was synthesized on the surface of nickel foam. Subsequently, a layer of graphdiyne was synthesized on this composite material through a coupling reaction, resulting in a novel interlayer composite material designated as CuCoLDH@GDY/NF. This structural configuration enhanced the material properties and improved stability. The catalyst exhibited exceptional performance in both OER and HER. The results demonstrated that the overpotentials of the CuCoLDH@GDY/NF dual-functional catalyst for HER and OER (without an oxidation peak) were 52 mV and 153 mV, respectively, at a current density of 10 mA cm⁻². CuCoLDH@GDY/NF generates a current density of 10 mA cm⁻² at a voltage of 1.63 V. Furthermore, the catalyst demonstrated remarkable durability during overall water splitting tests conducted for 48 h at a current density of 10 mA cm⁻². Given the high electrocatalytic performance and stability of CuCoLDH@GDY/NF, this study provides essential insights for the design of high-performance dual-functional catalysts.