Carbon aerogels (CAG) were synthesized by the pyrolysis of resorcinol-furfural based organic aerogels, derived from sol-gel polymerization of resorcinol and furfural using different catalysts followed by supercritical...Carbon aerogels (CAG) were synthesized by the pyrolysis of resorcinol-furfural based organic aerogels, derived from sol-gel polymerization of resorcinol and furfural using different catalysts followed by supercritical drying of as-prepared gels. Different catalysts viz. hydrochloric acid (HA), acetic acid (AcH) and hexamethylenetetramine (HMTA) of different concentrations were used for this purpose in order to study the role of different catalysts and the effect of R/C ratio (reactant to catalyst molar ratio) on the formation of organic gel monolith and their physical properties were investigated. Aerogels were thoroughly characterized by using CHN, FTIR, TG-DSC, XRD and SEM. A considerable reduction of gelation time and the formation of relatively denser organic gel were observed in the case of HMTA, which indicated the dual role (catalyst & cross-linking agent) of HMTA during the polymerization/polycondensation of resorcinol and furfural. Carbon aerogels obtained by using different catalysts showed BET surface area, average pore size, total pore volumes in the range of 438 496 m2/g, 17.9 22.4 ? and 0.20 0.27 cm3/g, respectively. The SEM images and results revealed the presence of different morphologies of carbon aerogels, obtained by using different catalysts. The HMTA catalyzed samples were found to have highest surface area with particles in smaller in size and well interconnected 3D carbon network.展开更多
文摘Carbon aerogels (CAG) were synthesized by the pyrolysis of resorcinol-furfural based organic aerogels, derived from sol-gel polymerization of resorcinol and furfural using different catalysts followed by supercritical drying of as-prepared gels. Different catalysts viz. hydrochloric acid (HA), acetic acid (AcH) and hexamethylenetetramine (HMTA) of different concentrations were used for this purpose in order to study the role of different catalysts and the effect of R/C ratio (reactant to catalyst molar ratio) on the formation of organic gel monolith and their physical properties were investigated. Aerogels were thoroughly characterized by using CHN, FTIR, TG-DSC, XRD and SEM. A considerable reduction of gelation time and the formation of relatively denser organic gel were observed in the case of HMTA, which indicated the dual role (catalyst & cross-linking agent) of HMTA during the polymerization/polycondensation of resorcinol and furfural. Carbon aerogels obtained by using different catalysts showed BET surface area, average pore size, total pore volumes in the range of 438 496 m2/g, 17.9 22.4 ? and 0.20 0.27 cm3/g, respectively. The SEM images and results revealed the presence of different morphologies of carbon aerogels, obtained by using different catalysts. The HMTA catalyzed samples were found to have highest surface area with particles in smaller in size and well interconnected 3D carbon network.
