Ammonia-assisted semicarbonization: a simple method to introduce micropores without damaging a 3D mesoporous carbon nanonetwork structure.

A simple and effective way to introduce micropores into skeleton of carbon aerogel (CA) without damaging its unique 3D mesoporous nanonetwork has been successfully developed by NH3-assisted semicarbonization. During the NH3-assisted semicarbonization process, nitrogen functional groups with high thermo-decomposable ability like pyrrolic/pyridine and pyridinic can be introduced into the semicarbonized aerogel framework by substituting oxygen functional groups with low thermo-decomposable ability like C═O quinone-type groups and then escape from the resultant CA framework during the subsequent carbonization, thus forming abundant micropores inside carbon framework under the circumstance of keeping wonderful stability of mesoporous nanonetwork structure. Compared with the traditional CA without NH3 assistance during semicarbonization, the as-prepared novel CA represents a much higher surface area (1100 vs 620 m(2) g(-1)) and a compatible mesopore structure. Meanwhile, such a NH3 treatment confers many useful nitrogen functional groups on the nanonetwork framework. The novel CA is then used as electrode material of supercapacitors and shows a much higher capacitance and comparable high capacitance retention as compared with the traditional CA.