Fig. 3. (a and b) EPR CB e^– signals of TTT–DTDA and TTT–BTDA under dark condition (black), during visible light irradiation (green) and after switching off the light (red). (c) UV-vis diffuse reflectance spectra of TTT–DTDA and TTT–BTDA. The inset shows Tauc plots and optical images of the COF powders. (d) Photo-polymerization of MMA using TTT–DTDA and TTT–BTDA, in presence of triethylamine at room temperature (argon atmosphere). Inset image shows the recyclability of TTT–DTDA for radical polymerization for three cycles.