Aerogel Essay

553 Words3 Pages
Aerogel * INTRODUCTIONBefore I start my talk, let me share a short story about my topic today. In1930s, a guy called Dr. Samuel Stephens Kistler has invented a new materials by removing the liquid from the gel through a process called supercritical drying. By using this process, he removed the liquid from silica gel under high pressure and high temperature. From this picture, the new materials that he invented is Aerogel.So for the following part, I would like to share the 3 aspects about aerogel such as the properties of aerogel, the types of aerogel and the applications of aerogel.Transition: Now, let’s begin my first main aspect – properties of aerogel. * BODY * First Main Point- properties of aerogel 1. Low density * Most aerogel gel are known as their extreme low densities. * For example the silica aerogel is only three times heavier than air and could be lighter than air by evacuating the air out from the pores. 2. Good thermal insulator * Aerogel consist of very small amount of solid silica. The solid that present is consisting of very small particles linked with three dimensional crystal lattice. This makes thermal transport through a solid portion in a indirect path and not effective. Transition: now let proceed to the second aspect – type of aerogel. * Second Main Point- type of aerogel 1. Carbon aerogel * Carbon aerogels have high porosity and surface areas are between 400-1000m2. They are often manufactured as composite paper. * Due to the high surface area, carbon aerogel are used to created supercapacitors. 2. Silica aerogels * Silica aerogel is the most common type of aerogel and the most extensively studied. It is a silica-based substance derived from silica gel. * It also strongly absorbs infrared radiation. It allows the construction of materials that let light go into buildings but trap
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