Carbon gels with unique morphologies

Abstract

Carbon gels are unique porous carbons, which are typically obtained through the carbonization of resorcinol–formaldehyde gels. They are practically an aggregate of nanometer-sized carbon particles. Nanopores, mostly in the size range of mesopores, exist between the particles. Smaller pores, micropores being the majority, also exist within the particles. Therefore, this material has a hierarchical pore system in which short micropores are directly connected to mesopores. This pore system can be tuned quite precisely, by simply adjusting the synthesis conditions, such as the amount of catalyst used for synthesis, and the drying conditions of the precursor RF gel. As the precursor RF gel is synthesized through a sol–gel transition, there is a high possibility that its morphology can be easily controlled. We have actually examined the possibility of controlling of the morphology of carbon gels, and have succeeded in obtaining them in the form of disks, microspheres and microhoneycombs. Details of such carbon gels are reported.