Pre‐Carbonization: An Efficient Route to Improve the Textural and Gas Sorption Properties of Nitrogen‐Enriched Nanoporous Polytriazine

Abstract An unprecedented approach to improve the CO₂ capture capacity by heating nitrogen enriched nanoporous polytriazine (NENP‐1) below the carbonization (pre‐carbonization) temperature has been invented. The NENP‐1 heated at 350 °C for 2 h (assigned as NENP‐1‐350) in argon atmosphere has improved specific surface area (SA_BET) marginally from 840 (NENP‐1) to 880 m² g⁻¹ (NENP‐1‐350). However, there was a substantial increase in the CO₂ capture capacity from 22.9 (NENP‐1) to 33.8 wt% (NENP‐1‐350) measured at 0 °C and 1 bar. Although, both the specimens have comparable SA_BET, the NENP‐1‐350 has larger pore volume of 1.10 cm³ g⁻¹ (as compared to 0.71 cm³ g⁻¹ in NENP‐1) and larger pore size distribution (PSD) along with the higher isosteric heat of adsorption that contributed for such a high CO₂ capture capacity. Unlike the CO₂ capture capacity in the NENP‐1‐350, there was only marginal increase in the hydrogen storage capacity from 2.30 to 2.47 wt% and methane sorption capacity from 1.8 to 1.9 wt% measured at −196 and 0 °C, respectively, as compared to the NENP‐1.