Preparation and characterization of a nitrogen-doped mesoporous carbon aerogel and its polymer precursor

Nitrogen-containing carbon aerogel was prepared from resorcinol-melamine-formaldehyde (R-M-F) polymer gel precursor. The polymer gel was supercritically dried with CO2, and the carbonization of the resulting polymer aerogel under nitrogen atmosphere at 900 degrees C yielded the carbon aerogel. The polymer and carbon aerogels were characterized with TG/DTA-MS, low-temperature nitrogen adsorption/desorption (-196 degrees C), FTIR, Raman, powder XRD and SEM-EDX techniques. The thermal decomposition of the polymer aerogel had two major steps. The first step was at 150 degrees C, where the unreacted monomers and the residual solvent were released, and the second one at 300 degrees C, where the species belonging to the polymer network decomposition could be detected. The pyrolytic conversion of the polymer aerogel was successful, as 0.89at.% nitrogen was retained in the carbon matrix. The nitrogen-doped carbon aerogel was amorphous and possessed a hierarchical porous structure. It had a significant specific surface area (890m(2)g(-1)) and pore volume (4.7cm(3)g(-1)). TG/DTA-MS measurement revealed that during storage in ambient conditions surface functional groups formed, which were released upon annealing.