| Carbon aerogels are a novel, low-density, porous, non-crystalline, monolithic, nanometer carbon materials, whose continuous network structures can be controlled and tailored at the nanoscale. Due to their special network structures, carbon aerogels take on some excellent properties, such as the larger specific surface area, the good electric conductivity, and the alterable density. Therefore, using carbon aerogels as electrode materials for electrochemical double-layer capacitor is extremely attractive and promising. Normally, the polymerization of resorcinol (R) with formaldehyde (F) catalyzed by sodium carbonate results in the formation of dark red, transparent RF organic aerogels via a sol-gel process, acid aging process, and supercritical fluid drying or ambient pressure drying. Upon pyrolysis of RF organic precursors at high temperature, the monolithic RF carbon aerogels can be obtained.This dissertation has firstly developed a new technology process to prepare carbon aerogels by employing new raw materials and new catalysts The microstructures of the new developed carbon aerogels was investigated by means of low-temperature N2 adsorption, IR, NMR, XPS, SAXS, TEM, SEM, Raman spectroscopy and TG etc. The synthetic mechanism of the new carbon aerogels was rationally inferred based on the primary experimental demonstration. Furthermore, using the prepared carbon aerogels as electrode materials, the corresponding electrochemical behavior was characterized by means of cyclic volammetry and impedance spectroscopy. The dependence of capacitances and impedance on the microstructure of carbon aerogel electrodes was discussed.In the present study, both calcium hydroxide and magnesium carbonate were firstly employed as the catalyst to prepare resorcinol-formaldehyde carbon aerogels. In comparison with sol-gel system catalyzed by potassium carbonate and sodium carbonate, the gel time was markedly shortened and the densities of the prepared carbon aerogels were obviously reduced. It was shown that the gel time and RF carbon aerogels properties were mainly determined by the catalyst content (R/Cat) and reactant concentration. The network structures of carbon aerogels catalyzed by Ca(OH)2 were more regular than that of carbon areogels catalyzed by KaCOa, Na2CO3. The difference between these two types of carbon aerogels resulted from the participation of metal positive ion in the polycondensation reaction during the sol-gel process.In the presence of sodium hydrate, the polymerization of mixture cresol (Cm) with formaldehyde resulted in the formation of low-density, monolithic, free-crack CmF organic and carbon aerogels. Due to the high reactant concentration the aquagel had a good strength.Hence, the aging process can be saved and the preparing times of aerogels was shortened for this sol-gel system. TEM showed that the mixture cresol aerogel had a three-dimensional network. In present experiments, the lowest density of CmF organic aerogel is 0.062 g/cm3, the density of the corresponding carbon aerogel is 0.090 g/cm3. Meanwhile, the synthetic mechanism of CmF aerogel was deduced firstly based on the primary experimental demonstation..Carbon aerogels can be prepared upon pyrolysis of the CmF organic precursors at 900 癈,which can inherit well the 3D network of the original organic aerogels. The pyrolysis process of the CmF aerogel was investigated firstly by means of IR technique. The results showed an infrared active vibration occured in the temperature range of 400-600 "C, which was corresponding to the tubstatic graphitized structure formed hi these aerogels. With the increasing pyrolysis temperature, the specific surface area as well as micropore surface area and total volume increased accompanied with the narrower pore size distribution. The microstructure parameters calculated by the a s-plot for aerogels showed a good agreement with that obtained from the BJH method. The orthogonal experiment for carbonization process indicated that the heating rate and the final carbonization temperature showed mo...
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