Decouple and Synergize: D‐π Conjugation‐Enabled Remote Electronic Tuning of M‐O Sites for Enhanced C‐H/O‐H Cleavage in HMF Electrooxidation

ABSTRACT Electrocatalytic 5‐hydroxymethylfurfural oxidation reaction (HMFOR) is a green biomass valorization route, yet its scalability is constrained by the intrinsically sluggish hydroxymethyl oxidation on transition‐metal‐based catalysts, which, unlike aldehyde oxidation, requires concurrent C‐H/O‐H cleavage and C(sp 3 ) → C(sp 2 ) rehybridization. However, current strategies lack atomic‐scale precision to accelerate this kinetics and establish clear structure‐performance relationships. Herein, M 3 (HHTP) 2 (M = Co, Cu) with atomically ordered and dispersed metal sites was designed to decouple intrinsic roles of M‐O sites in HMFOR. Building on this, bimetallic Co 1.8 Cu 1.2 (HHTP) 2 was constructed, harnessing d‐π conjugation for precise bidirectional long‐range electronic communication between spatially separated M‐O sites: Cu‐O kinetically accelerates the sluggish hydroxymethyl oxidation on Co‐O, while Co‐O reciprocally mitigates Cu‐O poisoning from excessive HMF adsorption, establishing a self‐sustaining electronic synergy. Meanwhile, differentiated OH − adsorption on the dual sites optimizes the H‐bond network, accelerating electrochemical‐chemical cycle at Co‐O. Ultimately, Co 1.8 Cu 1.2 (HHTP) 2 delivers a 2.7‐fold higher 2,5‐furandicarboxylic acid yield than Co 3 (HHTP) 2 and enables gram‐scale production of 99.4%‐pure 2,5‐furandicarboxylic acid via 2,5‐diformylfuran and 5‐hydroxymethyl‐2‐furancarboxylic acid pathways. This work establishes d‐π conjugation as a general strategy to decouple and synergize specific roles of spatially separated sites to overcome the rate‐determining step, providing a novel paradigm for rational catalyst design in complex multi‐step reactions.