Microporous carbons derived from melamine and isophthalaldehyde: One-pot condensation and activation in a molten salt medium for efficient gas adsorption.

ABSTRACT: In the present work, mixture of melamine and isophthalaldehyde undergo simultaneous polymerization, carbonization, and in situ activation in the presence of molten salt media through a single all-in-one route to design microporous carbons with high specific surface areas (~3000?m2/g). The effect of the activation temperature and molten salts on the polymerization process and final texture of the carbon was explored. Carbon materials prepared at 700?°C, in the presence of KOH (referred as MIK-700), exhibited a narrower pore-size distribution ~1.05?nm than those prepared in the presence of the eutectic KOH-NaOH mixture (MIKN). Additionally, MIK-700 possesses an optimum micropore volume (1.33?cm3/g) along with a high nitrogen content (2.66?wt%), resulting in the excellent CO2 adsorption capacity of 9.7?mmol/g at 273?K and 1?bar. Similarly, the high specific area and highest total pore volume play an important role in H2 storage at 77?K, with 4.0?wt% uptake by MIKN-800 (specific surface area and pore volume of 2984?m2/g and 1.98?cm3/g, respectively.) Thus, the facile one-step solvent-free synthesis and activation strategy is an economically favorable avenue for designing microporous carbons as an efficient gas adsorbents.

SUBMITTER: Rehman A 

PROVIDER: S-EPMC5904172 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature