Alloying Au into a Cu/Cu2O/nickel foam photoanode for solar-enhanced hydrogen production coupled with glucose oxidation

Abstract

The Cu/Cu₂O photoelectrocatalyst, possessing strong active centers and a narrow bandgap, has been considered a potential photoanode for photoelectrocatalytic hydrogen production coupled with glucose oxidation. However, its limited charge separation and solar utilization capability have been considered as bottleneck issues, restricting its performance. Herein, a novel Au/Cu/Cu₂O-decorated nickel foam (denoted as Au–Cu/NF) was tailored as a photoanode for the photoelectrocatalytic hydrogen production-coupled glucose oxidation reaction (Pe-GOR). This material was prepared via a glycerol-assisted hydrothermal method, resulting in the alloying of Au atoms into the Cu/Cu₂O/NF structure. The employed characterizations unveil the alloying of Au atoms into the structure via the formation of an Au–Cu alloy on the NF support through intimate linkages (e.g., Au–Cu–Ni), which unambiguously promotes solar light absorption and charge transport capabilities. Consequently, the Au–Cu/NF sample exhibits outstanding photoelectrocatalytic activity and stability in the Pe-GOR. Notably, the achieved Au–Cu/NF photoanode produces an average of 2.57 mmol H₂ h⁻¹ cm_geo⁻² at 1.62 V vs. RHE for 15 cycles within a total working time of 45 hours. The presented material demonstrates a novel strategy toward the utilization of photoelectrocatalysts for the solar-enhanced hydrogen production-coupled glucose oxidation reaction.