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

Herein, a Cu/Cu 2 O-decorated nickel foam (named Cu/Cu 2 O/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 Cu 2 O phases. Characterization results prove the presence of Cu and Cu 2 O phases on the NF support. Furthermore, positron annihilation spectroscopy measurements reveal the complete architecture of the material, in which Cu and Cu 2 O 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/Cu 2 O/NF-Gly for the HER and GOR. Consequently, the prepared Cu/Cu 2 O/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/Cu 2 O nanoparticle–decorated NFs to produce valuable chemicals in hydrogen production–coupled glucose oxidation systems.