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Author(s): Shih-Yuan Lu, Te-Yu Wei, Yu-Cheng Chang

Keywords: accelerated-gelation sol-gel process, barrett-joyner-halenda, barrett-joyner-halenda (bjh) pore volume, bet, bjh, brunauer-emmett-teller, brunauer-emmett-teller (bet), carbon nanofibers, density, extinction coefficients, fe-sem, fourier-transform infrared spectroscopy, fourier-transform infrared spectroscopy (ft-ir), ft-ir, high temperature, opacified monolithic aerogels, pore volume, porosity, scanning electron microscopy, scanning electron microscopy (fe-sem), specific surface area, supercritical drying, tga, thermal conductivity, thermal insulation, thermogravimetric analysis, thermogravimetric analysis (tga), tps technique, transient plane source, transient plane source (tps) method

Abstract: The main objective of this research project was to create a material with a very low thermal conductivity at high temperatures, for the conservation of energy in high temperature systems. To accomplish this goal, the researchers incorporated carbon nanofibers into the mesoporous network of monolithic aerogels, with up to a 20 wt.% through an accelerated-gelation sol-gel process. The synthesis process also involved the use of supercritical drying of the aerogels to prevent as much shrinkage as possible of the aerogel. The newly synthesized monolithic aerogels were tested at temperatures up to 500°C. The new materials were shown to have much more favourable thermal conductivities as compared to currently existing high temperature materials.

Reference: Journal of Physical Chemistry C 2009, 113, 7424-7428

DOI: 10.1021/jp900380q