N-doped microporous carbons derived from direct carbonization of K + exchanged meta -aminophenol–formaldehyde resin for superior CO 2 sorption

N-doped microporous carbons with uniform ultramicropores (∼0.50 nm) are facilely prepared by direct carbonization of K(+) exchanged meta-aminophenol-formaldehyde resin. These materials give an unprecedented CO2 uptake of 1.67 mmol g(-1) at 25 °C and 0.15 bar and superior CO2-over-N2 selectivity (50 : 1).