Aerogel Synthesis and Application

Aerogel has become a material of interest to scientists in recent decades due to its unique physical properties that give it the potential to improve technologies in a variety of fields. In particular, aerogels offer the lowest densities and the lowest thermal conductivities of any known solid. Silica-based aerogels were first synthesized in 1931 by Steven Kistler. Since then, many other types of aerogels have been created, including carbon-based and claybased aerogels. Silica-based aerogels are the simplest and most widely studied type of aerogel, with new uses and applications arising every day. As such, silica-based aerogels offer a unique platform on which to base further research in the small liberal-arts college setting. This project examined the process of synthesizing low-density silica-based aerogels. The goal was to create a reliable, non-toxic method, using inexpensive materials and equipment already owned by the Pomona College Physics Department. The science involved was built off of results achieved by the author in Physics 174: Contemporary Experimental Physics class at Pomona College in the spring of 2008. The recipe used to synthesize the aerogels was found on the Lawrence Berkely National Laboratory website [9]. Additions to the recipe were implemented as suggested on William Wood’s website [24]. The recipe incorporated the most recent technique in aerogel manufacturing, replacing tetramethylorthosilicate (TMOS) with tetraethylorthosilicate (TEOS). Both of the chemicals are precondensed silica precursors, with TEOS being the less toxic of the two. The gel molds were in the shape of cylinders so that both thin and thick disks could be created depending on desired speed of production, and desired further experimentation. Specific drying methods were based on Tousimis Samdri-PVT-3D critical point dryer manual and suggested techniques from Dr. Tousimis [27]. The scanning electron microscope was then used by Dr.