Electronic Structure Reconfiguration of Zn-NB Sites for Enhanced Fenton-Like Catalysis.

Despite growing interest in single-atom catalysts (SACs) for Fenton-like reactions, zinc (Zn)-based SACs remain unexplored due to the inherent inertness of Zn, whose fully occupied 3d electronic configuration limits redox activity. Here, we overcome this limitation by introducing boron (B) atoms to reconfigure the electronic structure of Zn-N coordination sites, yielding an activated catalyst denoted as Zn-NBC. This electronic modulation transforms inert Zn-N sites into catalytically active centers (Zn-NB ), enabling significantly enhanced Fenton-like activity. Compared to the unmodified Zn-N catalyst (Zn-NC), Zn-NBC exhibits a 26-fold increase in the rate of organic pollutant degradation. Density functional theory (DFT) calculations and experimental results reveal that Zn-NC and Zn-NBC exhibit distinct PDS adsorption behaviors, with B incorporation tuning both adsorption strength and electronic interactions at the Zn center. Crystal orbital Hamilton population (COHP) analysis further demonstrates that the Zn-NBC facilitates the activation of the S─O bonds in peroxydisulfate (PDS), promoting the generation of reactive oxygen species, including peroxide radicals and singlet oxygen. These findings establish a new paradigm for activating electronically inert metal centers and position Zn-NBC as a promising platform for efficient and sustainable environmental remediation.