Modulating Electron Transfer in Vanadium-Based Artificial Enzymes for Enhanced ROS-Catalysis and Disinfection

Abstract

Nanomaterials-based artificial enzymes (AEs) have flourished for more than a decade. However, it is still challenging to further enhance their biocatalytic performances due to the limited strategies to tune the electronic structures of active centers. Here, a new path is reported for the de novo design of the d electrons of active centers by modulating the electron transfer in vanadium-based AEs (VO_x -AE) via a unique Zn-O-V bridge for efficient reactive oxygen species (ROS)-catalysis. Benefiting from the electron transfer from Zn to V, the V site in VO_x -AE exhibits a lower valence state than that in V₂ O₅ , which results in charge-filled V-d_yz orbital near the Fermi level to interfere with the formation of sigma bonds between the V- $d_{z^2}$ and O-p_z orbitals in H₂ O₂ . The VO_x -AE exhibits a twofold V_max and threefold turnover number than V₂ O₅ when catalyzing H₂ O₂ . Meanwhile, the VO_x -AE shows enhanced catalytic eradication of drug-resistant bacteria and achieves comparable wound-treatment indexes to vancomycin. This modulating charge-filling of d electrons provides a new direction for the de novo design of nanomaterials-based AEs and deepens the understanding of ROS-catalysis.

Keywords: ROS-based biocatalysis; antibacterial and wound healing; artificial enzymes; electron modulation; inorganic nanomaterials.