Frontier Advances in Boosting the Fe-Based Nanozymes Catalytic Activity: From Nanoparticles to Single Atoms

Abstract

Natural enzymes boast high catalytic efficiency and specificity. However, their utility is often limited by several inherent drawbacks, including environmental instability, high production costs, and sensitivity to harsh conditions. To address these challenges, nanozymes have emerged as robust alternatives. Among them, Fe-based nanozymes stand out due to their biocompatibility, efficient Fe²⁺/Fe³⁺ redox cycling, and ability to mimic the activities of peroxidase (POD), oxidase (OXD), catalase (CAT), and superoxide dismutase (SOD). Their catalytic performance is intrinsically linked to atomic-scale structural features, driving a paradigm shift from traditional nanoparticles (NPs) to precisely engineered single-atom catalysts (SACs).This review systematically summarizes how structural precision governs the catalytic performance of Fe-based nanozymes.For NPs, the optimization strategies include size control, morphology engineering, surface modification, and composition adjustment. Those measures can enhance their activity by maximizing the active site exposure and substrate affinity. For SACs, a series of strategies for improving catalyst performance were summarized, including regulation of the coordination environment, metal-support interaction, and the species of metal active centers. These approaches through optimize electronic configurations, lower reaction energy barriers, and emulate natural enzymatic mechanisms to enhance the catalyst activity. However, challenges persist in scalable synthesis, operational stability, dynamic structure-activity characterization, and substrate selectivity. Future directions include real-time monitoring of catalytic processes and in situ studies to bridge the gap between nanozymes and natural enzymes.