Continuous-flow electrooxidation for scalable biomass upgrading over copper-supported CoFe Prussian blue analogues

Electrochemical biomass upgrading is a promising substitute for oxygen evolution reaction (OER) to generate valuable chemicals in conjunction with hydrogen generation. Pursuing highly efficient and durable electrocatalysts for significant concentration levels (≥ 50 mM) of biomass electrooxidation remains an enduring challenge. Herein, we introduce a robust Cu-supported CoFe Prussian blue analogue (CoFe PBA/CF) electrocatalyst, adept at facilitating high-concentration (50 mM) 5-hydroxymethylfurfural (HMF) oxidation into 2,5-furandicarboxylic acid (FDCA), achieving an exceptional HMF conversion (100%) with a notable FDCA yield of 98.4%. The influence of copper substrate and adsorption energy are therefore discussed. Impressively, the CoFe PBA/CF electrode sustains considerable durability in a continuous-flow electrochemical reactor designed for consecutive FDCA production, showcasing FDCA yields of 100/94% at flow rates of 0.4/0.8 mL·min-1 over 60 h’ uninterrupted electrolysis. This work provides a promising strategy to develop highly efficient and robust electrocatalysts for the consecutive production of high-value products coupled with green H2 production.