Self-Cascade Ce-MOF-818 Nanozyme for Sequential Hydrolysis and Oxidation

Mimicking efficient biocatalytic cascades using nanozymes has gained enormous attention in catalytic chemistry, but it remains challenging to develop a nanozyme-based cascade system to sequentially perform the desired reactions. Particularly, the integration of sequential hydrolysis and oxidation reactions into nanozyme-based cascade systems has not yet been achieved, despite their significant roles in various domains. Herein, a self-cascade Ce-MOF-818 nanozyme for sequential hydrolysis and oxidation reactions is developed. Ce-MOF-818 is the first Ce(IV)-based heterometallic metal-organic framework constructed through the coordination of Ce and Cu to distinct groups. It is successfully synthesized using an improved solvothermal method, overcoming the challenge posed by the significant difference in the binding speeds of Ce and Cu to ligands. With excellent organophosphate hydrolase-like (Km = 42.3 mu M, Kcat = 0.0208 min-1) and catechol oxidase-like (Km = 2589 mu M, Kcat = 1.25 s-1) activities attributed to its bimetallic active centers, Ce-MOF-818 serves as a promising self-cascade platform for sequential hydrolysis and oxidation. Notably, its catalytic efficiency surpasses that of physically mixed nanozymes by approximately fourfold, owning to the close integration of active sites. The developed hydrolysis-oxidation self-cascade nanozyme has promising potential applications in catalytic chemistry and provides valuable insights into the rational design of nanozyme-based cascade systems. A self-cascade Ce-MOF-818 nanozyme with dual active centers composed of Ce and Cu is developed for performing sequential hydrolysis and oxidation reactions. With exceptional organophosphate hydrolase-like and catechol oxidase-like activities, the nanozyme demonstrates superior hydrolysis-oxidation cascade efficiency compared to physically mixed catalysts. The developed nanozyme provides new insights into the rational design of nanozyme-based cascade systems.image