Cu–Sn Bimetallic Activated Carbon–Carbon Coupling for Efficient Furfural Electroreduction

Electrochemically driven carbon–carbon coupling utilizing renewable electricity under ambient conditions has emerged as an innovative approach for synthesizing high-value chemicals, which still faces inherent challenges such as low conversion rates and poor selectivity. While electroreducing furfural to hydrofuroin can produce high-quality biofuel, its efficiency need to be promoted. Herein, Cu–Sn bimetallic catalyst has been developed with a conversion rate of furfural of >97% and hydrofuroin selectivity of >67% through equilibrium of the interfacial intermediate *H and *fur-CHOH, which exhibits the greatest state-of-the-art overall performance. Characterization and theoretical calculation reveal that Cu serves as the active site for generating *fur-CHOH, whose electron density can be decreased by introducing Sn, and results in a higher *fur-CHOH coverage and a lower energy barrier of dimerization. Moreover, adding Sn also enables sluggish *H formation to balance interfacial *fur-CHOH and *H, leading to reduced hydrogenation byproducts. The as-developed approach provides valuable insights for optimizing other C–C electrocoupling reactions for the synthesis of high-value chemicals.