Facile one-pot synthesis of mesoporous carbon and N-doped carbon for CO2 capture by a novel melting-assisted solvent-free method

Abstract

A facile and efficient one-pot melting-assisted solvent-free method was successfully developed for the first time to produce hierarchically mesoporous carbon and nitrogen-enriched mesoporous carbon materials. This method used a very simple thermal treatment process instead of normally reported solvent-based preparations, thus making it potentially very applicable for fast and large scale production of mesoporous carbons. The obtained carbon materials were comprehensively characterized by X-ray diffraction, Raman spectroscopy, N₂ sorption, scanning electron microscopy, transmission electron microscopy, CHN analysis, X-ray photoelectron spectroscopy, and elemental mapping. The results show that the as-synthesized carbon materials possess well-developed hierarchical porous structures, uniform pore sizes, and high surface areas, and the specific structures can be adjusted by changing the temperature and duration of the thermal treatment process. Moreover, the resultant carbon material with a high surface area of 748 m² g⁻¹ exhibits excellent CO₂ capture properties with a capacity of 2.73 mmol g⁻¹ at 298 K and 1 bar, and a CO₂ selectivity of 21.6 under flue gas conditions. More importantly, due to the successful incorporation of large amounts of highly dispersed N in the carbon matrix (11.67%), the as-synthesized NMC sample exhibits a significantly enhanced CO₂ capacity of 1.66 mmol g⁻¹ with an excellent CO₂ selectivity of 240.7 at 348 K and 1 bar, revealing great promise for practical CO₂ capture applications.