Nitrogen-doped porous carbon prepared from a liquid carbon precursor for CO2 adsorption

摘要

We report a new carbonaceous material derived from a liquid precursor, polyethylenimine (PEI) by chemical activation using KOH. The PEI-derived activated carbon possesses typical microporosity with a high specific surface area. It also features rich nitrogen content and various nitrogen functional groups. It was found that at 1 bar the CO2 uptake of these PEI-derived carbons was 4.9-5.7 mmol g(-1) at 0 degrees C and 2.9-3.7 mmol g(-1) at 25 degrees C. Specifically, the CO2 adsorption capacity of the carbon activated at 600 degrees C was the highest, being 5.67 mmol g(-1) at 0 degrees C, atmospheric conditions. The PEI-derived carbons also exhibit very good stability during multi-cycle adsorption-desorption tests and a high selectivity of CO2 over N-2 at 25 degrees C.