Electrocatalysis of 5-hydroxymethylfurfural at cobalt based spinel catalysts with filamentous nanoarchitecture in alkaline media

This study reports the activity of cobalt based metal oxide electrode with spinel structure for 5-hydroxymethylfurfural (HMF) oxidation. For that purpose, the Co₃O₄ and NiCo₂O₄ electrode with filamentous nanoarchitecture were grown on Ni foam by a hydrothermal method and then characterized by means of SEM, TEM, and XPS analyses. During electrochemical oxidation of HMF, the role of Co³⁺ in Co₃O₄ and NiCo₂O₄ spinel structure was investigated by XANES. The filamentous nanoarchitecture of NiCo₂O₄ showed 99.6% 5-hydroxymethylfurfural (HMF) conversion efficiency with 90.8% selectivity on 2,5-furandicarboxylic acid (FDCA). The catalyst was successfully recycled up to three times, retaining over 80% of FDCA conversion efficiency. These results demonstrated the potential interest of NiCo₂O₄ anodic catalyst, prepared via hydrothermal method, for production of high-valued chemical from biomass-derived compounds via electrochemical techniques.