One-Pot Solvent-Free Strategy for the Facile and Fast Synthesis of Highly Enriched Nitrogen-Doped Carbons

Hierarchical porous nitrogen-doped carbons (HNCs) were successfully prepared by a facile and highly efficient one-pot solvent-free method through the in situ copolymerization of resorcinol, p-phthalaldehyde, melamine, and Pluronic F127. This method involves only a simple thermal treatment process, thus making it a potential choice for fast and large scaled production of HNCs. The obtained HNCs were comprehensively characterized by X-ray diffraction, Raman spectroscopy, N2 sorption, scanning electron microscopy, transmission electron microscopy, CHN analysis, X-ray photoelectron spectroscopy, elemental mapping, and CO2 adsorption. The results show that HNCs possess well-developed hierarchical porous structures and highly dispersed nitrogen contents. Even though the incorporated nitrogen content is as high as 11.80 wt %, the HNCs still exhibit high porosity and surface area. Due to the incorporation of a large number of nitrogen species in carbon frameworks, the HNC exhibits excellent CO2 adsorption performance with CO2 capacity of 1.66 mmol/g at 348 K and 1.0 bar, and CO2/N2 selectivity of 241 under flue gas conditions. In addition, on the basis of the experimental and simulation results, it is believed that among different nitrogen species the pyridinic nitrogen is likely to be the most favorable for CO2 adsorption.