CO2 Adsorption Performance of Nitrogen-enriched Porous Carbon Materials Synthesized Using the g-C3N5 Template Strategy

Graphical This study develops nitrogen-enriched porous carbon materials using chitosan and g-C 3 N 5 through hydrothermal carbonization and pyrolysis. The optimized adsorbent (S200-6) exhibits a high CO 2 adsorption capacity (3.98 mmol/g at 298 K, 1 bar), large specific surface area (2306 m 2 /g), and excellent selectivity (14.3 for CO 2 /N 2 ). Carbon capture and storage are crucial because of the environmental issues caused by excessive CO 2 emissions. Porous carbon is considered the most promising adsorbent. The precise adjustment of the pore structure and surface active sites of samples is necessary to increase their CO 2 adsorption capacity. In this study, chitosan-based N-doped porous carbon materials were developed using g-C 3 N 5 as the self-sacrificial templating agent and N dopant, respectively, via hydrothermal and pyrolytic activation methods. CO 2 adsorbents possessing a large specific surface area (2084–2450 m 2 /g), microporous structure, and N content were synthesized by varying the hydrothermal temperature and g-C 3 N 5 ratio. The maximum CO 2 adsorption capacity of the highest-performing adsorbent S200-6 was 3.98 mmol/g at 298 K and 1 bar. After 10 CO 2 adsorption and desorption cycles, S200-6 retained 94% of its initial adsorption capacity, indicating its excellent reusable stability. This study demonstrates the feasible preparation of porous carbon materials through a combination of g-C 3 N 5 with hydrothermal and pyrolytic activation methods and reveals the application potential of S200-6 as a CO 2 adsorbent.