General Electrocatalytic Plastic and Biomass Refining via Synergistic Carbon–Carbon Bond Cleavage Over Oxygen Vacancies and Ni ³⁺ –O Octahedral Motifs in Tailored Spinel Nickel Cobalt Oxide

ABSTRACT Electrooxidation of recyclable carbon resources from plastics and biomass offers a promising route for value‐added conversion via C–C bond cleavage to yield small organic acids. However, developing electrocatalysts with broad substrate applicability is hindered by limited C–C bond cleavage selectivity and sluggish kinetics. Herein, we constructed a NiO x –NiCo 2 O 4 ‐U electrocatalyst with substantial oxygen vacancies, in which NiCo 2 O 4 tends to adopt an inverse spinel configuration, leading to abundant Ni 3+ –O octahedra with e g occupancy close to unity. This catalyst facilitates two C–C bond cleavage pathways: *OH mediated processes and in situ generation of active NiOOH during electrooxidation. For the electrooxidation of lactic acid (monomer of polylactic acid) to acetic acid, NiO x ‐NiCo 2 O 4 ‐U grown on nickel foam achieves a high Faradaic efficiency of 99.2% at 1.45 V versus RHE and a high yield of 5432 µmol h −1 cm −2 at 600 mA cm −2 , along with excellent stability. Benefiting from the optimized vacancy modulation and Ni–O coordination structure, the NiO x ‐NiCo 2 O 4 ‐U exhibits superior C–C bond cleavage capability, enabling the highly selective electrooxidation of at least 10 oxygenated organic molecules, including ethylene glycol, glycerol, and glucose. This work provides a design strategy for versatile electrooxidation catalysts and may support industrial applications integrating waste plastics and biomass derivatives.