Preparation and Characterization of Polyamides and Nitrogen-doped Carbons for Enhanced CO₂ Capture

Porous organic polymers possessing CO₂-philic moieties have captured attention of the researchers due to efficient adsorption of gas molecules. By the condensation of organic rigid and contorted precursors, amide-linked organic framework polymers with low skeletal density have been prepared via a cost-effective protocol. Polyamide chains were synthesized via low temperature condensation of 2,4,6-triamino-1,3,5-triazine with terephthaloyl chloride and isophthaloyl chloride to yield PA-1 and PA-2, respectively. The synthesized polymers were further carbonized at 600°C to fabricate nitrogen-doped carbon materials (PA1-600 and PA2-600). The as-prepared materials were analyzed by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), thermal gravimetric analysis (TGA), CHN elemental analysis, textural analysis, and CO₂ adsorption measurements. The maximum CO₂ uptake determined is 42.85 mg/g at 273 K and 1 bar. The triazine rings with basic nitrogen atoms and amide bonds in the main chain are responsible for CO₂ capture by the polymers.