Solvent-free self-assembly synthesis of N-doped ordered mesoporous carbons as effective and bifunctional materials for CO2 capture and oxygen reduction reaction

Abstract Traditional processes for the synthesis N-OMCs as effective and bifunctional materials for CO2 capture and oxygen reduction reaction (ORR) are unfavorable from the perspective of green chemistry. Herein, we reported the synthesis of N-OMCs through a solvent-free self-assembly route. A N-doped ordered mesoporous polymer (N-OMP) as the carbon precursor was first synthesized from manually mixed terephthalaldehyde, m-aminophenol and Pluronic F127. The precursors were then mechanically mixed with g-C3N4 for carbonization at different temperatures to result in a series of N-OMCs. The resultant N-OMCs were found to have well-developed ordered mesoporosity, and high nitrogen contents of 5.82–6.53 wt%. As a result, the CO2 capacities of N-OMCs can reach as high as 2.46 mmol/g at 0 °C and 0.15 bar, and the adsorption of CO2 by N-OMCs also shows high selectivities towards N2 as well as excellent recycling performance. The ORR activity of N-OMCs is very impressive, with the onset potential of 1.003 V, and half-wave potential of 0.858 V. Overall, the ORR activity of N-OMCs is much better than that of commercial Pt/C catalyst.