In-situ charge polarization effect of copper(II) ion-coordination covalent organic framework induced aerobic PET-ATRP in aqueous phase

Abstract

Covalent organic frameworks (COFs) are ideal heterogeneous photocatalytic platforms offering fascinating spaces for manipulation given their clearly defined structures along with pre-customizable skeletons. Herein, an imine-based COF Im-oMe featuring N and O sites allowing the integration of Cu ions via coordination bonds in local regions of the skeleton is reported for aerobic photoinduced electron/energy transfer atom transfer radical polymerization (PET-ATRP) in the aqueous phase. Cu@Im-oMe of anchored Cu ions is capable of triggering skeleton localized polarization effects, producing greater dipole moment driving force and facilitating the charge separation and transport to enhance its photopolymerization performance. Meanwhile, the system does not require additional addition of transition metal halides, and remains highly active after 3 cycles. The present work expands the feasible design methods and strategies of heterogeneous photocatalysts available for precision production of polymers in open-air environments.