Air-Stable Radical Organic Cages as Cascade Nanozymes for Enhanced Catalysis

Small. 2023 Feb;19(5):e2206127. doi: 10.1002/smll.202206127. Epub 2022 Nov 28.

Abstract

The pursuit of single-assembled molecular cage reactors for complex tandem reactions is a long-standing target in biomimetic catalysis but still a grand challenge. Herein, nanozyme-like organic cages are reported by engineering air-stable radicals into the skeleton upon photoinduced electron transfer. The generation of radicals is accompanied by single-crystal structural transformation and exhibits superior stability over six months in air. Impressively, the radicals throughout the cage skeleton can mimic the peroxidase of natural enzymes to decompose H2 O2 into OH· and facilitate oxidation reactions. Furthermore, an integrated catalyst by encapsulating Au clusters (glucose oxidase mimics) into the cage has been developed, in which the dual active sites (Au cluster and radical) are spatially isolated and can work as cascade nanozymes to prominently promote the enzyme-like tandem reaction via a substrate channeling effect.

Keywords: biomimetic catalysis; cascade nanozymes; radical cages; structural transformation; substrate channeling.