Poly{tris[4-(2-thienyl)phenyl]amine} and poly[tris(4-carbazoyl- 9-yl phenyl)amine] conjugated microporous polymers as absorbents for highly efficient iodine adsorption

Highlights: • We investigated the iodine adsorption performance of PTPATTh and PTPATCz. • The PTPATTh shows lower specific surface area (S_BET = 594 m² g⁻¹) than PTPATCz (S_BET = 894 m² g⁻¹) does. • The PTPATTh (3.13 g g⁻¹) shows higher adsorptivity than PTPATCz (2.56 g g⁻¹). • The phenyl ring, N and S heteroatoms and charge-transfer interactions are the effective sorption sites to iodine. - Abstract: Poly{tris[4-(2-thienyl)phenyl]amine} (PTPATTh) and poly[tris(4-carbazoyl-9-yl phenyl)amine] (PTPATCz) are thiophene-based and carbazole-based conjugated microporous polymers with triphenylamine as cores. Here we present detailed evidence of highly efficient and iodine capture in both CMPs. Thanks to the propeller-like structure, high porosity, extended π-conjugation and electron-rich characteristics, the both CMPs display efficient, adsorption of I₂ in vapor (up to 3.13 and 2.56 g g⁻¹) and in solution. Two ways to release the adsorbed iodine were explored: either slow release into ethanol or quick release upon heating (with a high degree of control). In addition, the both CMPs could be recycled while maintaining 70% iodine uptake capacity (up to 85%). Thus making the resulting CMPs ideal absorbent materials for iodine capture to address environmental issues.