Control of mesoporosity of carbon gels prepared by sol–gel polycondensation and freeze drying

摘要: Abstract Carbon cryogels were prepared by pyrolyzing resorcinol–formaldehyde (RF) cryogels, which synthesized via the sol–gel polycondensation of resorcinol with formaldehyde in a slightly basic aqueous solution followed freeze drying. Various RF changing amount reactant, catalyst and water used polycondensation. The porous properties evaluated nitrogen adsorption method scanning electron microscopy (SEM). mesoporosity was related to ratio (C/W). Although mesopores reduced size some extent pyrolysis, carbon also C/W. For under condition C/W ⩽70 mol/m 3 , peak radius mesopore distribution, BET surface area volume decreased increase On other hand, for >70 it difficult prepare mesoporous carbon.