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

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.