Light induced construction of porous covalent organic polymeric networks for significant enhancement of CO2 gas sorption

Abstract

Herein, we report morphology-controlled porous polymeric materials for enhanced CO₂ capture, which was achieved using the topochemical polymerization of dipeptide functionalized diphenylbutadiynes. The topochemical reaction was executed to control the morphology of the synthesized dipeptide appended diarylbutadiyne derivatives on a solid surface. Topochemical polymerization involves the formation of polydiacetylene due to the presence of hydrogen bonding between the amide groups and intermolecular π–π stacking interactions in their self-assembled state, which was established using UV-Vis, Raman and IR spectroscopy. The change in morphology of the two dipeptide functionalized diphenylbutadiyne (DPB) was confirmed by scanning electron microscopy. Porosity was developed after UV irradiation of the diacetylene-based dipeptide appended bolaamphiphiles. Interestingly, after UV irradiation, the porous covalent organic polymers 1 and 2 show 24.22 times and 12 times enhanced N₂ gas adsorption than their parent compounds 1 and 2, respectively. The surface area of the porous covalent organic polymers 1 and 2 was enhanced 21.68 times and 5.54 times than their parent compounds 1 and 2, respectively. Polymer 1 exhibits 4.23 times the CO₂ capture ability than compound 1 and polymer 2 shows 4.1 times the CO₂ capture ability than compound 2. This study highlights the controlled synthesis of light induced porous covalent organic polymers with high surface area used for efficient CO₂ storage applications.