Efficient nitrogen doped porous carbonaceous CO_(2) adsorbents based on lotus leaf

In this work, the waste biomass lotus leaf was converted into N-doped porous carbonaceous CO_(2) adsorbents. The synthesis process includes carbonization of lotus leaf, melamine post-treatment and KOH activation. For the resultant sorbents, high nitrogen content can be contained due to the melamine modification and advanced porous structure were formed by KOH etching. These samples were carefully characterized by different techniques and their CO_(2) adsorption properties were investigated in detail. These sorbents hold good CO_(2) adsorption abilities, up to 3.87 and 5.89 mmol/g at 25 and 0 °C under 1 bar, respectively. By thorough investigation, the combined interplay of N content and narrow microporous volume was found to be responsible for the CO_(2) uptake for this series of sorbents. Together with the high CO_(2) adsorption abilities, these carbons also display excellent reversibility, high CO_(2)/N 2 selectivity, applicable heat of adsorption, fast CO_(2) adsorption kinetics and good dynamic CO_(2) adsorption capacity. This study reveals a universal method of obtaining N-doped porous carbonaceous sorbents from leaves. The low cost of raw materials accompanied by easy synthesis procedure disclose the enormous potential of leaves-based carbons in CO_(2) capture as well as many other applications.