Integrated Electrolysis for Biomass Valorisation and Hydrogen Generation by Catalysts and System Engineering

The urgent need for clean and sustainable energy solutions has placed hydrogen (H2) at the center of global decarbonisation strategies. While water electrolysis is a mature method for hydrogen production, its commercial deployment remains limited by the sluggish oxygen evolution reaction (OER) at the anode, which not only consumes significant energy but also produces oxygen, a low-value by-product. To address this limitation, the BioHydroCat project proposes a hybrid electrolyser that integrates hydrogen evolution reaction (HER) at the cathode with the selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), a high-value monomer for bio-based plastics, at the anode. Compared to conventional thermal catalysis, electrochemical oxidation proceeds under milder conditions and with a lower onset potential (0.3 V vs. RHE), but existing approaches are hindered by costly and unstable catalysts, low biomass utilisation (5–10 mM HMF), low current density (~10 mA cm⁻²), and high post-processing costs associated with acid-based recovery of FDCA from concentrated alkaline electrolytes.BioHydroCat will address these challenges by developing gadolinia-doped ceria (GDC) supported catalysts, combined with mechanistic insights derived from density functional theory (DFT) and operando techniques. Furthermore, a pulse-assisted membraneless electrolyser will be designed to minimise membrane degradation, enhance energy efficiency, and reduce overall system costs. By bridging materials engineering, electrochemical process engineering, and computational modelling, this project will enable sustainable co-production of FDCA and hydrogen in dilute alkaline media (0.3 M) with concentrated HMF feedstocks, thereby reducing the need for costly acid-based recovery. The proposed work is fully aligned with the EU Green Deal, circular economy, and sustainable development goals, while reinforcing Europe’s scientific excellence in advanced electrochemical technologies