Converting Glycerol into Valuable Trioses by Cu δ+ -Single-Atom-Decorated WO 3 under Visible Light.

Photocatalytic selective oxidation under visible light presents a promising approach for the sustainable transformation of biomass-derived wastes. However, achieving both high conversion and excellent selectivity poses a significant challenge. In this study, two valuable trioses, glyceraldehyde and dihydroxyacetone, are produced from glycerol over Cu δ+ -decorated WO 3 photocatalyst in the presence of H 2 O 2 . The photocatalyst exhibits a remarkable five-fold increase in the conversion rate (3.81 mmol ⋅ g -1  ⋅ h -1 ) while maintaining a high selectivity towards two trioses (46.4 % to glyceraldehyde and 32.9 % to dihydroxyacetone). Through a comprehensive analysis involving X-ray photoelectron spectroscopy measurements with and without light irradiation, electron spin resonance spectroscopy, and isotopic analysis, the critical role of Cu + species has been explored as efficient hole acceptors. These species facilitate charge transfer, promoting glycerol oxidation by photoholes, followed by coupling with OH - , which are subsequently dehydrated to yield the desired glyceraldehyde and dihydroxyacetone.