Coordination Engineering in Fe-Mn Dual-Atom Nanozyme: Yielding ROS Storm to Efficiently Promote Wound Healing

Abstract

Multidrug-resistant bacterial infections have become a global public health issue. To solve this dilemma, single-atom nanozymes have been used as versatile antibiotics. However, the efficacy of individual nanozyme is hindered by their limited catalytic activity and antibacterial effect. Herein, a novel N₃-Fe₁-Mn₁-N₂S nanozyme (Fe/Mn-SNC), with neighboring Mn and Fe dual single-atom pairs decorated on yolk-shell-like carbon skeleton, is constructed through partial modulation of Fe-Mn dual site coordination by sulfur atoms. The developed Fe/Mn-SNC possesses superior multienzyme-like cascade activities (oxidase-, superoxide-, and peroxidase-like activities). It catalyzes the conversion of O₂ into O₂^·− through its oxidase-like activity, which is then decomposed into H₂O₂ by its superoxide-like enzyme properties. Ultimately, ·OH is generated under the influence of peroxidase-like activity. This process effectively kills bacteria without the addition of H₂O₂, contributing to the overcoming of bacterial resistance issues. Density functional theory calculations indicate that the direct coordinated S atom enhances the oxidase-like activity. The Fe-Mn dual-atomic site provides an additional active site for the enhancement of the superoxidase- and peroxidase-like activities. The Fe/Mn-SNC, with high antibacterial effect and biosafety, showing its wide potential applications in medical technology and consumer care. This work opens a new avenue for designing multifunctional single-atom nanozymes for antibacterial applications.