Coordination Number Regulation of Molybdenum Single-Atom Nanozyme Peroxidase-like Specificity

•A class of MoSA–Nx–C nanozymes are designed and implemented•The peroxidase-like specificity is regulated by Mo–Nx coordination numbers•MoSA–N3–C single-atom nanozyme has superior exclusive activity•The mechanism coordination-number-dependent POD-like elucidated Nanozymes, which nanomaterials with enzyme-like characteristics, combine the advantages biocatalysts. Although stability durability these comparable to those natural enzymes, unsatisfactory still limits their wide application as alternatives enzymes. Controlling targeted performance traditional extremely challenging owing intrinsic structural complexity nanomaterials. Here, we report theoretical design experimental realization a series heterogeneous molybdenum nanozymes. Their well numbers single Mo sites. A MoSA–N3–C specific activity demonstrated. This work unravels structure-selectivity relationships provides an effective strategy for rational Nanozymes promising but use remains limited poor specificity. Overcoming this controlling due systems. We (named MoSA–Nx–C), wherein find that The resulting catalyst shows behavior. It achieves behavior via homolytic pathway, whereas MoSA–N2–C MoSA–N4–C catalysts have different heterolytic pathway. enzymatic attributed geometrical structure differences orientation frontier molecular orbitals toward peroxidase mimics. study demonstrates peroxidase-specific precise regulation properties. enzymes biocatalysts,1Wu J. Wang X. Q. Lou Z. Li S. Zhu Y. Qin L. Wei H. Nanomaterials characteristics (nanozymes): next-generation artificial (II).Chem. Soc. Rev. 2019; 48: 1004-1076Crossref PubMed Google Scholar can catalyze degradation inorganic oxygen species even organic substrates.2Huang Ren Qu Nanozymes: classification, catalytic mechanisms, regulation, applications.Chem. 119: 4357-4412Crossref Scopus (767) Scholar,3Gao M. Zheng Xu Liu W. 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