Kinetic elucidation of F-Niδ+-O coordination motifs enriched nickel oxide nanosheets for biomass valorization

Rational design of heteroatom-doped catalysts with prominent reaction kinetics holds immense potential for enhancing biomass electrooxidation processes. Here, we introduce a F-doped NiO nanosheet architecture enriched with F-Ni δ+ -O coordination motifs as an advanced electrocatalyst for the oxidation of 5-hydroxymethylfurfural (HMF). XPS depth profiling and differential charge density calculations reveal that the distinctive F-Ni δ+ -O configuration induces asymmetric charge redistribution at Ni sites, effectively reducing the activation energy for Ni 3+ OOH species and their subsequent interaction with HMF. Meanwhile, pH-dependent and in-situ Raman measurements demonstrate that F sites function as proton relays, facilitating proton transfer and enabling efficient proton-coupled electron transfer kinetics. The synergistic electronic and proton effects endow excellent catalytic performance, with an oxidation current density of 66.45 mA cm −2 and a reaction rate of 5.23 × 10 −4 s −1 , far higher than that of the original NiO. Notably, the catalyst retains over 95 % Faradaic efficiency and yield of 2,5-furandicarboxylic acid (FDCA) after twenty consecutive cycles. This work establishes a dual regulation strategy via heteroatom doping to simultaneously modulate electronic configuration and proton transfer dynamics, offering novel insights into the design of high-performance electrocatalysts for biomass valorization.