Photoelectrocatalytic Reforming of Polyol-based Biomass into CO and H₂ over Nitrogen-doped WO₃ with Built-in Electric Fields.

CO and H₂ evolution from renewable and abundant biomass represent a sustainable way, but is challenged to be produced under mild conditions. Herein, we propose to produce CO and H₂ from biomass via a divided photoelectrochemical (PEC) cell at room temperature. Nitrogen doped tungsten trioxide (N-WO₃ ) photoanode reforms biopolyols to CO and H⁺ , and platinum cathode reduces H⁺ to H₂ , achieving CO evolution rate of 45 mmol m^-2  h^-1 (>75 % gas selectivity) and H₂ evolution rate of 237 mmol m^-2  h^-1 with purity >99.99 % from glycerol. The nitrogen doping induces structure polarity of WO₃ photoanode, leading to the formation of an internal electric field which promotes the separation and transfer of the photoinduced charges and improves PEC efficiency. A wide range of biopolyols, such as ethylene glycol, xylose, fructose, glucose, sucrose, lactose, maltose, and inulin were effectively converted into CO and H₂ . This work provides a promising method to produce highly pure H₂ together with CO from biomass.