Lattice Distortions Promoting the In-Depth Reconstruction of Ni-Based Electrocatalysts with Enriched Oxygen Vacancies for the Electrochemical Oxidation of 5-Hydroxymethylfurfural toward 2,5-Furandicarboxylic Acid

The electrocatalytic 5-hydroxymethylfurfural (HMF) oxidation reaction (HMFOR) toward 2,5-furandicarboxylic acid (FDCA) has been considered a promising approach for the substitution of the energy-consuming and hazardous oxygen evolution reaction and for the valorization of renewable biomass. However, it is limited by the susceptibility of HMF to the oxidative environment and requires efficient electrocatalysts. Herein, a NiMo complex (NiMo-N) is provided as the precatalyst for the HMFOR, exhibiting favorable performances with a current density of 450 mA·cm^-2 achieved at an anodic potential of 1.4 V vs RHE (similarly hereinafter) with 50 mmol/L (mM) HMF and over 95% HMF conversion and FDCA FE for at least five cycles. Combined with <i>quasi situ</i> and <i>in situ</i> analysis, it is confirmed that the extensive lattice distortions in the precatalyst facilitate the in-depth reconstruction, increasing the accessible Ni sites and defective oxygen vacancies (O_v), which would promptly convert to high-valence Ni and active O species during the reaction. The improved performance is then attributed to the incorporation of the improved chemisorption and dehydrogenation ability of HMF by the as-evolved active sites.