A Hyper-Cross-Linked Aerogel with Rigid Conjugated Polymers as Building Blocks for Efficient Iodine Capture

Porous organic polymers are typically synthesized through coupling reactions between multifunctional monomers. While rich-pore structures can be generated with long building blocks, the synthesis of molecules with functional groups of large spatial separation is challenging. Herein, we report a strategy using conjugated polymers as the long and rigid building blocks. A hyper-cross-linked polymer was synthesized through a click reaction between the internal alkyne units in conjugated polymers and a triazido-compound to give an organogel with a hierarchical porous structure. Benefitting from the rich π electrons and aromatic structures of the hyper-cross-linked polymer networks, the organic aerogel derived from the rigid conjugated polymer-based organogel exhibits a fast adsorption rate and high adsorption capacity for iodine in both aqueous and gas phases. The capture efficiency of the aerogel for iodine in saturated iodine aqueous solution exceeded 80% within 5 min, and the adsorption equilibrium capacity of 3.28 g g^–1 for iodine vapor was achieved within 60 min. In addition, the iodine-loaded aerogel has excellent retention in air and can be recycled after thermal release.