Regulating the H2O2 Activation Pathway on a Well-Defined CeO2 Nanozyme Allows the Entire Steering of Its Specificity between Associated Enzymatic Reactions

Nanozymes are promising alternativesto natural enzymes, but theiruse remains limited owing to poor specificity. For example, CeO2 activates H2O2 and displays peroxidase(POD)-like, catalase (CAT)-like, and haloperoxidase (HPO)-like activities.Since they unavoidably compete for H2O2, affectingits utilization in the target application, the precise manipulationof reaction specificity is thus imperative. Herein, we showed thatone can simply achieve this by manipulating the H2O2 activation pathway on pristine CeO2 in well-definedshapes. This is because the coordination and electronic structuresof Ce sites vary with CeO2 surfaces, wherein the (100)and (111) surfaces display nearly 100% specificity toward POD-/CAT-likeand HPO-like activities, respectively. The antibacterial results suggestthat the latter surface can well-utilize H2O2 to kill bacteria (cf., the former), which is promising for anti-biofoulingapplications. This work provides atomic insights into the synthesisof nanozymes with improved activity, reaction specificity, and H2O2 utilization.