Earth‐Abundant CuWO4 as a Versatile Platform for Photoelectrochemical Valorization of Soluble Biomass Under Benign Conditions

Here, a nanosheet‐structured CuWO4 (nanoCuWO4) is demonstrated as a selective and stable photoanode for biomass valorization in neutral and near‐neutral solutions. nanoCuWO4 can be readily prepared by a solid phase reaction using nanosheet‐structured WO3 as the template. Several substrates, including glucose, fructose and glycerol, are investigated to reveal the wide applicability of nanoCuWO4. The activity and product distribution trends in biomass valorization are investigated at different pH by taking advantage of the promising stability of nanoCuWO4 in a wide pH range. Product analyses confirm that formate production with a Faradaic efficiency (FE) of 76 ± 5% and glycolate production with an FE of 61 ± 8% can be achieved by glucose and fructose valorization at pH 10.2, respectively. On the other hand, glyceraldehyde and dihydroxyacetone (DHA) are the main products in the glycerol valorization, accounting for an FE of over 85% at pH 7. Notably, nanoCuWO4 has the highest FE of DHA in photoelectrochemical (PEC) glycerol valorization compared to WO3 and BiVO4 at neutral pH. The oxidation routes and mechanism of glycerol valorization on nanoCuWO4 are also under investigation. The co‐production of H2 and value‐added chemicals is finally demonstrated using a photovoltaic cell connected to a nanoCuWO4‐based PEC glycerol valorization system. CuWO4 is demonstrated as a versatile, selective and stable photoanode for photoelectrochemical (PEC) biomass valorization in neutral and near‐neutral. Glucose, fructose and glycerol are investigated as the substrate, with formate, glycolate, glyceraldehyde and dihydroxyacetone, respectively, as the main valorization product. The cogeneration of H2 and value‐added chemicals is also successfully established by a standalone photovoltaic‐ PEC glycerol valorization system.