Search

Persistent radical covalent organic frameworks (COFs) have exhibited great application potential in the fields of photocatalysis, magnetism, and biology. However, there is still a lack of a simple, green, and effective way to produce persistent radical COFs. Here, we synthesized two sp2 carbon-covalent organic frameworks (sp2C-COFs) with persistent triphenylamine radical cation (TPA+•), which can be generated by simple light irradiation since the effective donor–acceptor heterojunction is formed in ordered skeleton. The number of persistent TPA+• will increase with the intensity of light irradiation and the photogenerated electrons generated simultaneously can be consumed by O 2 to form reactive oxygen species, which can be then used to carry out the oxidative organic transformations under visible light. In addition, femtosecond-transient absorption spectra prove that the difference in the structure of the two radical cation sp2C-COFs will significantly influence the charge recombination rate, so that the materials show different catalytic efficiency. [Display omitted] • Two sp2 C-COFs with persistent radical cation are designed and synthesized. • The radical cation and ROS(O2–•) can be generated by simple light irradiation. • Two sp2 C-COFs display superior photocatalytic performance in organic transformation. • The relationship between structure and performance is explored by fs-TA spectra. [ABSTRACT FROM AUTHOR]