Operando Surface Ligands Boost Pt Nanozyme Activity for H₂O₂ Catalysis via Bridged Electron Transfer

Nanozymes, while possessing greater stability and durability than their natural counterparts, still face limitations of low catalytic activity and inefficient production. Here, we report a one-step method for the efficient construction of highly active nanozymes. The photolysis of butanedione was leveraged to generate surface-functionalized metal nanozymes. The in situ generated surface acetate (Ac) ligands serve as electron bridges between the substrates to boost the electron transfer, thus drastically improving the catalytic activity. The resulting Ac-Ptzyme, with a precisely tuned surface Ac content, demonstrated a peroxidase-like activity superior to that of the natural horseradish peroxidase and was approximately 200 times greater than that of Fe3O4. This superior activity endowed the Ac-Ptzyme with enhanced performance for visually monitoring the oxidative stress in bloom-forming cyanobacterial cells and for killing pathogenic bacteria in biofilm. This work paves a path to the facile synthesis of high-activity nanozymes for catalysis.