Spatially Adjacent Cu Single Atoms and Au Clusters for Photocatalytic Selective Oxidation of Ethylene Glycol Coupled with Hydrogen Generation

The photocatalytic oxidation of ethylene glycol (EG) and water splitting to glycolic acid (GA) coupled with H 2 evolution is promising for solar-to-chemical conversion but suffers from poor selectivity and activity. Herein, we construct a TiO 2 -based photocatalyst with spatially adjacent Cu single atoms (Cu SA ) and Au clusters (Au C ) via an in situ adsorption-pyrolysis and subsequent photodeposition strategy. Electron microscopy and X-ray absorption fine structure spectroscopy confirm the atomically dispersed Cu sites with spatially adjacent Au clusters. The electron microscopy, X-ray photoelectron, and in situ Raman spectroscopy reveal that Cu SA modulates the electronic and geometric structures of Au C sites. The optimized Au C -Cu SA /TiO 2 exhibits excellent performance for EG oxidation to GA coupled with H 2 production. Mechanistic studies demonstrate that Au C activates interfacial water to generate reactive oxygen species for selective EG oxidation, while adjacent Cu SA facilitates electron enrichment and proton reduction for H 2 evolution. This work provides a dual-active-site interfacial synergy strategy for efficient photocatalytic redox coupling.