Low‐Potential Generation of High‐Valence Metal Sites Activates Lattice Oxygen for Ampere‐Level 5‐Hydroxymethylfurfural Electrooxidation

ABSTRACT Electrocatalytic oxidation of 5‐hydroxymethylfurfural (HMF) to 2,5‐furandicarboxylic acid (FDCA) offers a sustainable route for biomass valorization, yet maintaining high Faradaic efficiencies (FE) at industrially‐relevant current densities remains challenging. Here, we report a rationally engineered nickel‐cobalt nitrate hydroxide with an edge‐rich and through‐pore structure, which rapidly reconstructs at exceptionally low potentials into an active NiCoOOH phase enriched with high‐valence metal sites. Combining isotope labeling experiments, molecular probe studies, and first‐principles calculations reveals that these high‐valence metal sites activate otherwise inert lattice oxygen to form reactive oxygen intermediates ( * O lat ‐O • ). These intermediates significantly reduce steric hindrance in the transition state, thereby lowering the activation barriers for O─H and C─H bond cleavage during the oxidation of HMF. This breakthrough enables the catalyst to achieve ampere‐level current densities of 1520 mA·cm −2 at 1.60 V vs. RHE, while maintaining a near‐quantitative FE FDCA of 97.7 ± 0.7% even at 1000 mA·cm −2 . Practical applicability is demonstrated in an anion‐exchange membrane electrolyzer, which operates stably for 100 h with single‐pass FDCA yields exceeding 98%. These findings establish the potential of lattice oxygen activation as a foundational design strategy for developing high‐performance electrocatalysts tailored to industrial‐scale biomass refineries.