Nitrogen-functionalized microporous carbon nanoparticles (N-MCNs) are prepared by direct carbonization of a novel polymer obtained from the Schiff base reaction of terephthalaldehyde and m-phenylenediamine. The carbonization temperature plays a crucial role in the porosity, surface chemistry and capacitive performance for the carbons. N-MCN850 sample shows a much larger specific surface area of 1938 m(2) g(-1), a higher specific capacitance of 397 F g(-1) and 145 F g(-1) at the current density of 0.1 and 100 A g(-1) in 6 M KOH aqueous electrolyte, respectively. The results indicate its outstanding capacitive behavior and ultrahigh-rate performance. In addition, the electrode shows excellent cycling stability along with 98% of the initial specific capacitance after 5000 charge/discharge cycles. (C) 2014 Elsevier Ltd. All rights reserved.