Facile synthesis of nitrogen-enriched microporous carbons derived from imine and benzimidazole-linked polymeric framework for efficient CO2 adsorption

•In this work, microporous polymer was synthesized via ecomically favorable avenue.•The resulting polymer, IBLP, was carbonized to design a series of carbon materials.•The fabricated materials show better textural properties in comparison to the precursor polymer.•On exploiting the carbon materials as effective CO2 adsorbents, we observed an excellent performance with reversible adsorption-desorption phenomenon.

Microporous organic polymers containing heteroatoms are considered as promising substrates for CO2 capture and separation with a tangible effect on the atmosphere and clean energy applications. In the present work, we have reported a cost-effective strategy for designing a series of carbonized products by high-temperature treatment of an imine and benzimidazole linked polymer (IBLP). The resulting materials exhibit a high surface area with narrow micropores. CO2 adsorption measurements reveal a notable uptake capacity up to 130.4, 98.4, and 87.5 mg/g at 273, 298, and 308 K, respectively, along with the high isosteric heats of adsorption (30.4-32.2 kJ/mol). Presence of micropores and heteroatom in the solid adsorbents with the high thermal stability accompanied with excellent CO2/N2 selectivity proclaimed the nitrogen-enriched carbon as promising candidates for CO2 scrubbing technology.