Photoelectrochemical Decomposition of Lignin Model Compound on a BiVO4 Photoanode

Abstract The photoelectrochemical decomposition of lignin model compounds at a BiVO 4 photoanode is demonstrated with simulated sunlight and an applied bias of 2.0 V. These prototypical lignin model compounds are photoelectrochemically converted into the corresponding aryl aldehyde and phenol derivatives in a single step with conversion of up to ≈64 % over 20 h. Control experiments suggest that vanadium sites are electrocatalytically active, which precludes the need for a redox mediator in solution. This feature of the system is corroborated by a layer of V 2 O 5 deposited on BiVO 4 serving to boost the conversion by 10 %. Our methodology capitalizes on the reactive power of sunlight to drive reactions that have only been studied previously by electrochemical or catalytic methods. The use of a BiVO 4 photoanode to drive lignin model decomposition therefore provides a new platform to extract valuable aromatic chemical feedstocks using solar energy, electricity and biomass as the only inputs.