Figure 2.
(a) β-Cyclodextrin (β-CD)-based porous organic polymer (TFN-CDP) derived from aromatic nucleophilic substitution reaction (SNAr) between β-CD and tetrafluoroterephthalonitrile (TFN). Pictorial representation of TFN-CDP polymer (right) employed for micropollutant removal from water. (b) Postsynthetic modification of TFN-CDP polymer (highly selective toward cationic and neutral guests) to amine-functionalized TFN-CDP-red polymer, which shows a high affinity toward anionic guests, including polyfluorinated alkyl substances (PFASs). (c) Schematic representation of PDC-CDP synthesis obtained through the polyaddition reaction between β-CD and 1,4-phenylene diisocyanate (PDC). (d) Plausible mechanism for the rapid sequestration of methylene blue (MB) dye in the hierarchically porous framework (PDC-CDP, left) and photocatalytic degradation of the adsorbed MB dye in the aqueous dispersion of TiO2-doped PDC-CDP upon photoirradiation at 365 nm (right).