Cu/Cu2O Nanoparticle–Decorated Nickel Foam as an Electrocatalyst for Hydrogen Evolution and Glucose Oxidation

Herein, a Cu/Cu2O-decorated nickel foam (named Cu/Cu2O/NF-Gly) is synthesized and used as a bielectrocatalyst for the hydrogen evolution reaction (HER) and glucose oxidation reaction (GOR). This material is synthesized via a facile glycerol-assisted hydrothermal method, in which glycerol functions as a critical agent, preserving the NF support and driving the growth of Cu and Cu2O phases. Characterization results prove the presence of Cu and Cu2O phases on the NF support. Furthermore, positron annihilation spectroscopy measurements reveal the complete architecture of the material, in which Cu and Cu2O phases are directly bonded to the NF support via Cu–Ni and Ni–O–Cu bonds, respectively. Density functional theory calculations also prove the structural stability and strong capabilities of Cu/Cu2O/NF-Gly for the HER and GOR. Consequently, the prepared Cu/Cu2O/NF-Gly electrode exhibits excellent electrocatalytic activities in both reactions. Impressively, when the prepared catalyst is employed as the cathode and anode, it exhibits a remarkable hydrogen evolution rate of 2.75 mmol·h–1·cm–2, corresponding to the remarkable Faradaic efficiency of 100.1% for hydrogen in hydrogen production–coupled glucose oxidation applications at 1.7 V vs reversible hydrogen electrode. Our results underscore the potential of using Cu/Cu2O nanoparticle–decorated NFs to produce valuable chemicals in hydrogen production–coupled glucose oxidation systems.