Strategies to increase the selective electrocatalytic oxidation of 5-hydroxymethylfurfural to produce 2,5-furanedicarboxylic acid

Electrocatalytic 5-hydroxymethylfurfural oxidation reaction (HMFOR) to produce 2,5-furanedicarboxylic acid (FDCA) offers a promising strategy to produce high value chemicals. Herein, CuO(S-ER-1.5) with excellent catalytic performance was prepared by anodic oxidation, sulfidation and electrochemical reconstruction on the substrate of copper foam. The experimental results of catalytic performance showed that CuO(S-ER-1.5) can catalyze HMFOR with a high current density (200 mA cm −2 ) at a low potential (1.48 V vs RHE) and exhibit outstanding stability. The open-circuit potential time test displayed that more HMF molecules were adsorbed in the Helmholtz layer of CuO(S-ER-1.5), which proved that the CuO(S-ER-1.5) could improve the kinetic adsorption of HMF. The electrochemical impedance spectroscopy further showed that CuO(S-ER-1.5) had faster reaction kinetics than Cu(OH) 2 precursor. The product analysis showed that CuO(S-ER-1.5) electrocatalytic HMFOR followed the DFF path, and the catalytic mechanism was explored by the three-step rate deconvolution procedure. It was found that CuO(S-ER-1.5) electrocatalytic HMFOR was dominated by direct oxidation reaction. This work provides a valuable guidance for the synthesis of value-added chemicals FDCA by electrocatalytic HMFOR.