The construction of silicon–oxygen bonds has been highlighted as an exciting achievement in organosilicon and green chemistry, but their synthetic efficiency has great improvement potential, so it is crucial to explore and achieve an effective approach for synthesizing such compounds. In this study, we successfully prepared the highly dispersed platinum single-atom catalyst (Pt SAC/N-C) through a coordination-assisted strategy with a mixture of ligands (H₂bpdc and H₂bpydc), which were used for the O-silylation of alcohols with silanes. The strong coordination between Pt²⁺ and the Pyridine N at the skeleton of UiO-67 plays a critical role in accessing the atomically isolated dispersion of Pt sites. Without the assistance of the H₂bpydc ligands, the Pt/ UiO-67-bpdc precursor is prone to aggregation during the pyrolysis process, resulting in the formation of Pt nanoparticles. Aided by advanced characterization techniques of high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and X-ray absorption fine structure (XAFS) spectroscopy, it has been demonstrated that atomically dispersed Pt was formed on the UiO-67 through a local structure of four-coordinated Pt-N₄, exhibiting a high actual Pt loading content (0.6962 wt.%). In the oxidation of silanes, the Pt SAC/N-C catalyst showed a high turnover frequency (TOF) value (up to 9,920 h⁻¹) when the catalyst loading decreased to 0.005%. Excellent performance was maintained during recycling experiments, indicating high stability of the catalyst.

Considering intracellular hydrogen peroxide (H₂O₂) plays pivotal roles in the regulation of serial biological processes, the in-situ detection of intracellular H₂O₂ has attracted an extensive attention. In the present work, an atomically dispersed diatomic active sites Nanozymes (FeN₃/PtN₄-single-atom nanozymes (SAzyme)) was prepared exhibiting enhanced peroxidase-like activity. The obvious synergistic effect between Fe–Pt heteronuclear diatomic active sites was confirmed by series of characterization and density functional theory (DFT). The peroxidase-like activity of Fe-sites could be substantially enhanced by the bonded Pt-sites via the modulation effect. As a consequence, the gap between the d-band centre (ε_d) of Fe 3d orbitals and the Fermi energy level was narrowed and the electronic interaction could be strengthened, leading to a lower free energy barrier and a lower activation energy as well as fortified metal–O bonding in the kinetic pathway. Therefore, the constructed FeN₃/PtN₄-SAzyme exhibited higher peroxidase-like activity than that of FeN₄-SAzyme. The FeN₃/PtN₄-SAzyme-assisted oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) facilitated the colorimetric detection of dopamine (DA), an important biomolecule. The linear detection range and limit of detection (LOD) of DA and H₂O₂ were 1–10 μM, 0.01–1.0 mM and 0.109 μM, 7.97 μM, respectively. In addition, the constructed SAzymes were also applied for the in-situ detection of intracellular H₂O₂, expanding the application scope of the newborn SAzymes.