Synthesis and electrochemical performance of N-doped carbon aerogels with super-high specific surface area

Activated N-doped carbon aerogel (N-ACA) is synthesized by the sol-gel polycondensation of resorcinol with formaldehyde using the melamine as nitrogen source, and then the carbon derivative being activated in CO2 flow. The surface morphology and porous structure are analyzed using scanning electron microscopy (SEM) and N2 adsorption at 77 K. The contained nitrogen of surface and monolith is tested by X-ray photoelectron spectroscopy (XPS) and elemental analysis. The electrochemical performances of N-dope carbon aerogels as electrodes are confirmed using constant-current charge-discharge test (GV), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It reveals that the rich porous structure and the chemical state of nitrogen functionalities have crucial effect on the electrochemical performance of the electric double-layer capacitors. The appropriate CO2 activation can increase the number of micropores and mesopores as well as the specific surface area (4082 m2g-1).Furthermore, the presence of amount of pyrrolic nitrogen is reinforced in the electron donor capacity. The specific capacitance of N-ACA electrode is up to 211.9 Fg-1 and retains about 98% after 500 charge-discharge cycles.