In Situ Synthesis of Porphyrin-Based Hyper-Cross-Linked Sub-nanometer Porous Polymer for Carbon Dioxide Adsorption Applications

The immobilization of porphyrin molecules within porous materials using cost-effective methods holds significant importance. Herein an in situ synthetic strategy involves the condensation of imidazole aldehyde and pyrrole to create 5,10,15,20-tetra(1H-imidazol-5-yl)porphyrin, followed by a cross-coupling reaction to effectively integrate porphyrin units into a porous polymer (RSS-2). RSS-2 exhibited heightened permanent porosity, with a surface area measuring 655 m2/g, noteworthy nanoporosity at a pore size of 6 Å, and enhanced thermal stability, evidenced by a decomposition temperature of 430 °C. Moreover, RSS-2 exhibited a high adsorption capacity of 79 cm3.g–1, remarkable CO2 affinity (Qst 38 KJ.mol–1), and a CO2/N2 Henry's selectivity of 255.