Spontaneous Corrosion Induced Scalable Fabrication of Bayberry‐Like Ni@Ni₃S₂ Core–Shell Catalysts for 5‐Hydroxymethylfurfural Oxidation

Abstract Electrocatalytic oxidation of biomass‐derived 5‐hydroxymethylfurfural (HMF) presents a promising pathway for synthesizing the value‐added chemical, 2,5‐furandicarboxylic acid (FDCA). However, it is still lack of scalable strategies to fabricate electrocatalysts with high activity and selectivity. Herein, a bayberry‐like Ni@Ni₃S₂ core–shell catalyst is prepared via a spontaneous corrosion strategy for HMF electro‐oxidation. The Ni₃S₂ shells with abundant electron‐deficient Ni sites facilitate the generation of high‐valence Ni³⁺OOH active species. Additionally, the in situ oxidation of S²⁻ to SO₄²⁻ enhances the electron and proton transport capacity. Both high‐performance liquid chromatography (HPLC) and density functional theory (DFT) analyses reveal that Ni@Ni₃S₂ preferentially selects the 2,5‐dicarboxyfurylfuran (DFF) pathway due to the lower reaction energy barrier from HMF to DFF, and the rate‐determining step of DFF oxidation to generate 5‐formylfuran‐2‐carboxylic acid (FFCA) is significantly accelerated. Consequently, the yield of FDCA and Faraday efficiency are found to be 99.20% and 99.35%, respectively, and they still reach 88.79% and 90.33% after ten cycles, showing excellent stability. Moreover, a mass production of 13.97 g Ni@Ni₃S₂ is successfully synthesized using the spontaneous corrosion strategy. This work offers a valuable reference for designing scalable and high‐performance catalysts by manipulating reaction routes to achieve efficient biomass conversion.