Electrochemical Production of 2,5-Furandicarboxylic from 5-Hydroxymethylfurfural Using Ultrathin Co(OH)2 on ZIF-67

Electro-oxidation of 5-hydroxymethylfurfural (5-HMF) to 2,5-furandicarboxylic acid (FDCA) requires a high applied potential to achieve a high FDCA yield. In this work, ultrathin Co(OH)2 on the ZIF-67 metal–organic framework has been designed as an efficient electrocatalyst for a high FDCA yield at a low applied potential. The obtained Co(OH)2@ZIF-67 electrocatalyst provides excellent catalytic performance with a 90.9% conversion, a 81.8% yield of FDCA, and 83.6% of faradaic efficiency. Importantly, the applied potential of the reaction has been reduced to 1.42 V (vs RHE), which is one of the lowest potentials among electrocatalysts developed for this reaction. The reaction mechanism has been proposed based on high-performance liquid chromatography analysis and DFT calculations, which reveal the importance of the 5-HMF binding mode on product selectivity. The synergistic effect from the Co(OH)2 active surface and ZIF-67 porous support on the high catalytic efficiency has been investigated by electrochemical surface area and pore characteristic analysis to provide a better understanding on the catalyst.