Electrocatalytic hydrogenation offers a sustainable route to upgrade biomass, as exemplified by the conversion of furfural to high-value alcohols. Current catalysts remain inadequate due to the poor modulation of active hydrogen, which leads to side reactions at high current densities. Here, we report that an atomic Mo-O-Cu interface promotes active hydrogen generation and modulates hydrogen adsorption, enabling a unique synergistic hydrogenation mechanism at the interface. By optimization of interface density, an optimal balance is achieved between hydrogen generation and utilization. A low-density Mo1O4/Cu catalyst exhibited outstanding performance in an anion exchange membrane (AEM) flow electrolyzer, delivering a 97% Faradaic efficiency and 54.4 mol m-2 h-1 production rate of furfuryl alcohol. The process demonstrated scalability in a 25 cm2 flow electrolyzer, successfully producing 8.34 g of furfuryl alcohol in 5 h. Our work provides insights into synergistic catalysis at the atomic interface, advancing the development of green, sustainable electrocatalytic biomass hydrogenation technologies.
Cao et al. (2026) studied this question.