Photo-enhanced nanozyme with self-cascade catalysis enhances peroxidase-like activity for alcohol discrimination.

[Display omitted] • Cyano-defective carbon nitride nanozyme with photo-enhanced peroxidase-like activity is reported. • Hydroxyl radical-involved self-cascade catalytic mechanism is revealed. • Sensing array based on carbon nitride nanozyme is constructed for alcohol discrimination. Nanozymes have been widely reported to serve as promising alternatives to enzymes. However, insufficient activity is one prominent challenge that limits their further exploitation of applications. To address this issue, photoenzymes, that can borrow solar energy to boost catalysis, inspire the exploration of nanozyme catalysis upon illumination. Herein, a cyano-defective carbon nitride (CCN) nanozyme with photo-enhanced peroxidase-like (POD-like) activity was reported, where the photo-activation enables the 4.15-fold activity enhancement. Based on in situ characterizations, a self-cascade mechanism was proposed, where CCN can catalyze H 2 O 2 into hydroxyl radical (•OH) upon illumination and subsequently capture •OH to generate absorbed hydroxyl (*OH) for further catalysis in the dark. Taking advantage of the photo-enhanced activity, a sensing array was successfully constructed for alcohol discrimination. These findings not only set the foundation for photo-enhanced nanozymes but also highlight their potential for practical applications. [ABSTRACT FROM AUTHOR]