First PEM photoelectrolyser for the simultaneous selective glycerol valorization into value-added chemicals and hydrogen generation

The photoelectrocatalytic (PEC) valorization of glycerol is emerging for the co-generation of hydrogen and value-added organics like glyceraldehyde (GAD) or dihydroxyacetone (DHA). In this work, we have designed, tested and optimized a pioneering photoelectrolyser with a non-noble metal-based photoanode (WO3), operating in near-neutral conditions and using a proton-exchange membrane (PEM) which ensures the elution of a purified hydrogen stream from the cathode side while selectively oxidizing glycerol on the anode. The influence of light irradiation, external bias and cell temperature has been investigated, leading to GAD and DHA production rates of 11.1 and 5.2 mmol m−2 h−1 at 60 ºC and 1.2 V, along with 44.0 mmol H2 m−2 h−1. The long-term stability of the photoelectrolyser has also been validated and the particularities of this system with respect to other conventional devices have been discussed. PEC stands as a promising sustainable technology for the simultaneous H2 generation and biomass valorization. [Display omitted] •The first PEM PEC cell for glycerol valorization and H2 generation was developed.•A selective WO3 photoanode, a H+ -exchange membrane and near-neutral pH were applied.•Simultaneous anodic C3s and cathodic H2 production was optimized at 60ºC and 1.2 V.•PEC favours glycerol upgrading while electrocatalysis favours mineralization.•The synergy between photo- and electrocatalysis stands PEC as a promising technology.