Active site microenvironment engineering in M–N–C single-atom nanozymes: from precision regulation to mechanistic insights

X-ray absorption fine structure (XAFS) and transmission electron microscopy (TEM) with density functional theory (DFT) calculations, the structure-electronic-catalytic performance relationship within the microenvironment is elucidated, revealing the intrinsic logic of microenvironmental regulation in optimizing catalytic pathways. Current research still faces challenges such as the difficulty of precise microenvironment regulation, insufficient understanding of dynamic catalytic mechanisms, and unclear multi-factor synergistic mechanisms. Future efforts should focus on innovative precision control technologies, high spatiotemporal resolution characterization techniques, multi-factor synergistic regulation systems, and interdisciplinary integration. This will propel M-N-C nanozymes from empirical regulation to precision design, providing theoretical foundations and technical references for their large-scale applications in biomedicine, environmental remediation, and energy conversion.