Facile synthesis of nitrogen-doped porous carbon for supercapacitors

A very simple, activation-free method for preparing nitrogen-doped porous carbon with high surface area for supercapacitors by direct pyrolysis of a nitrogen-containing organic salt, ethylenediamine tetraacetic acid (EDTA) disodium magnesium salt, in an inert atmosphere is presented. As the pyrolysis temperature increases from 500 to 900 degrees C, both the BET surface area and pore volume of the disodium magnesium EDTA-derived carbons increase and reach up to 1811 m(2) g(-1) and 1.16 cm(3) g(-1), respectively, while the nitrogen content decreases from 11.14 at.% to 1.13 at.%. The carbon obtained at a moderate pyrolysis temperature of 700 degrees C possesses a balanced surface area (1258 m(2) g(-1)) and nitrogen content (5.43 at.%), exhibits high capacitance (281 F g(-1)), good rate capability (196 F g(-1) at 20 A g(-1)) and cycle durability in 6 mol L-1 KOH aqueous electrolytes.