Poly(triazine-co-pyrrole)-based conjugated microporous polymers for carbon dioxide capture

Abstract

Nowadays, conjugated microporous polymers (CMPs) are among the superior porous materials for carbon dioxide (CO₂) capture. The objective of this study was to accomplish oxidative copolymerization of 2,4,6-tris(5-bromothiophene-2-yl)-1,3,5-triazine and pyrrole in the presence of iron(III) chloride to produce a series of conjugated microporous polymers, TP-CMP-1, TP-CMP-2 and TP-CMP-3 for CO₂ capture applications. The monomers were employed at different molar ratios; the polymerization proceeded at room temperature, and subsequently, under solvothermal conditions to form a microporous network. The chemical structure of these TP-CMPs was ascertained using FTIR and solid ¹³C NMR techniques. The TP-CMPs were further characterized for thermal and morphological studies and subsequently evaluated for CO₂ adsorption capacity. All the TP-CMPs showed exceptional thermal stability with decomposition temperatures ranging from 314 to 390 °C. Moreover, these TP-CMPs exhibited a Brunauer–Emmett–Teller (BET) surface area of up to 556 m² g⁻¹, and CO₂ adsorption of up to 1.09 mmol g⁻¹ at 298 K under 1 bar pressure. The high surface area facilitated great interactions with CO₂ molecules and enhanced carbon dioxide capture.