Synthesis of N-doped hierarchically ordered micro-mesoporous carbons for CO2 adsorption

Influences of porous carbon’s physicochemical properties on CO 2 adsorption vary with CO 2 pressure. The clarification of such complicated influences will undoubtedly be beneficial to the design and synthesis of carbonaceous adsorbents. To this end, in the current work we synthesized a series of N-doped hierarchically ordered micro-mesoporous carbons (NHOMCs). Ordered mesoporous polymer was synthesized with a solvent-free method using F127 as the soft template. After removing F127, the polymer was activated with KHCO 3 in the presence of urea at 700–800 °C. The obtained NHOMCs inherited the ordered structure of the polymer, and exhibited high surface area and nitrogen content. Synergistic effects of urea and KHCO 3 on nitrogen content and textural properties were discussed and revealed. At 25 °C, high CO 2 uptakes of 4.02 mmol/g (1 bar) and 15.42 mmol/g (20 bar) were achieved by the NHOMCs. We then systematically investigated the correlation between CO 2 uptake and physicochemical properties. The decisive factors of CO 2 uptakes at different pressures (1 bar, 5 bar, 10 bar, 20 bar) were analyzed. We believe the current work will provide helpful insights into the research of porous carbons for CO 2 adsorption.