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Carbon airgel is a new lightweight materials, nano-porous, amorphous carbon, has many excellent properties (such as electrical conductivity, thermal insulating properties, porosity, etc.), can be applied to a catalyst carrier, electric adsorption desalination, adsorbents, chromatographic filler instrument, hydrogen storage material, is also Supercapacitors ideal electrode material and lithium battery. Carbon airgel since 1989 after the birth of twenty years time, has been widespread national attention and research, currently in the selection of raw materials, manufacturing process, and specific applications, etc. With a considerable degree of improvement and innovation. The traditional preparation of carbon aerogels by resorcinol and formaldehyde as raw materials, but because of the high price of resorcinol, limiting its application of carbon aerogels prepared. In order to reduce costs and improve the market competitiveness of carbon aerogels, This selection of phenolic homologues in the most inexpensive price phenol as raw material base as a catalyst, a small amount of resorcinol as a nucleating agent and the crosslinking reaction in aqueous phase reaction with formaldehyde carbon aerogels obtained through the two-step method. This paper examines the different amounts of resorcinol catalyst amount of alkali doping on the impact, as well as the subsequent carbon aerogels prepared morphology, density, volume shrinkage and carbonization yield of macroscopic properties such as impact, and through scanning electron microscopy, nitrogen adsorption-desorption isotherms, TGA and other means to analyze its effects on microstructure of carbon aerogels. The results show that adding a small amount of resorcinol can greatly reduce the formation of a transparent organic base catalyst, the amount of gel required; a small amount of resorcinol (10%, 20%) is added, the carbon airgel The slight decrease in cell content micropores and macropores introducing a small amount of alkali catalyst can be reduced to reduce the density of the resulting carbon aerogels and volume shrinkage; resorcinol when a relatively large amount (30%) is added When the mesoporous carbon airgel significantly reduced levels, macroporous content increased significantly, reducing the amount of alkali catalyst has increased the density of the resulting carbon aerogels and volume shrinkage. This article also uses constant current charge-discharge experiments investigated the resulting carbon aerogels at different current densities electrochemical performance, found that when the current density increases from 1mA to 50mA, the pure phenol specific capacitance of carbon airgel from 146.2 F / g dropped to 125.1F / g, while adding a small amount of resorcinol specific capacitance of carbon airgel from 177.1 F / g slightly decreased to 166.5 F / g, results showed that a small amount can be increased by adding resorcinol corresponding carbon gas condensate gum capacitance, especially at high current density can increase the capacitive properties.
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