A series of highly microporous carbon materials was produced by carbonization of a triazine-based covalent organic polymer (TCOP) followed by carbonization and CO2 physical activation. The N-containing porous COP was prepared from easily available economic monomer precursors via a simple Friedel-Crafts reaction, which produced a predominantly microporous structure with a high surface area. Carbonization at 600-900 degrees C produced predominantly microporous carbons with a narrow pore size distribution in the range of 0.5-1.5 nm. Upon further activation using CO2, more micropores were formed, accompanied by an increase in the surface area (to 2003 m(2) g(-1)) and the nitrogen level in the carbon structure was maintained at ca. 2 wt%. The electrochemical properties of the samples were measured by employing a three-electrode system with 6 M KOH electrolyte. Among the prepared carbon samples, the electrode fabricated using the carbon activated at 900 degrees C (AC-900) had a specific capacitance of 278 F g(-1) at a current density of 1 A g(-1), which is significantly higher than that of a commercial activated carbon (130 F g(-1)) and ranks among the highest reported so far. This improved performance was attributed to the highly microporous structure of the nitrogen-doped carbon with a narrow pore size distribution. (C) 2018 Elsevier Ltd. All rights reserved.