Spatially Ordered Dual‐Atom Nanozymes for Mimicking Substrate‐Induced Conformational Locking in Natural Enzymes

Abstract

ABSTRACT Natural metalloenzymes achieve exceptional catalytic efficiency and specificity through substrate‐induced conformational locking (SCL) across bimetallic sites. However, most nanozymes lack such adaptive microenvironments and dynamic regulatory capabilities. We reported a spatially ordered bimetallic nanozyme, o‐FePd DAN, with a Cl‐FeN 3 C‐PdN 3 catalytic center that emulated the SCL mechanism through directional electron transfer (DET) and axial microenvironment reconfiguration. Density functional theory (DFT) calculations showed that the Fe‐Pd configuration provides optimal H 2 O 2 adsorption, the lowest O‐O dissociation energy, and enhanced activation of reactive oxygen species (ROS). Meanwhile, operando X‐ray absorption spectroscopy reveals the formation of a bridged structure at the bimetallic site during catalysis, establishing a dynamic charge‐transfer pathway that switches the dominant reaction from ROS‐mediated oxidation to a DET process driven by the bridged structure. This adaptive electron modulation arises from d‐orbital hybridization and the emergence of new active states near the Fermi level in the Cl‐FeN 3 C‐PdN 3 site. Furthermore, o‐FePd DAN is integrated into a three‐channel visual origami sensing (Tc‐VOS) platform for multichannel genotyping of human papillomavirus (HPV) subtypes. This work demonstrates a strategy for constructing spatially ordered bimetallic DANs that reproduce the SCL effect of natural enzymes and establish a dynamic, conformationally adaptive catalytic mechanism for nanozyme design.