SOL-GEL SYNTHESIS OF AEROGELS
Experiment 1 consists of synthesizing a nanostructured material using sol-gel science. The process to form the final material requires a drying step, which includes either ambient drying or supercritical drying. The different drying procedures create what are known as aerogels or xerogels. Figure 1 shows different types of aerogels produced by authors: a semi-transparent low-density aerogel and a highly transparent, ultra-low density aerogel. Aerogels are very high surface area metal oxides that have been called frozen smoke due to their transparency and ultra-low densities. They are obtained by supercritical drying. Xerogels are a lower surface area version of aerogels and have a greater density relative to their aerogel form due to drying at ambient conditions. For experiment I, we have formulated the exact compositions that the students will synthesize for experiment I. This includes formation of a silicon oxide aerogel and xerogel. via hydrolysis and condensation of metal alkoxides.