Aerogel: World’s Lightest Solid
To start: The Aerogel
Having a variety of descriptive nicknames such as; frozen smoke, solid smoke, solid air, solid cloud, and blue smoke, aerogel is a relatively new and absolutely unique substance that has arrived in our lives, so welcome!
As the most simple explanation goes; aerogel is a substance that is derived from the liquid component for the gel which in fact has been replaced with gas without a noteworthy change in the gel composition, which results in a solid with extremely low density and low thermal conductivity.
The historical discovery of aerogel does not go a long way, it was invented in 1931 by Samuel Stephens Kistler, an American scientist and chemical engineer, from a bet. Kistler claimed that he could replace the liquid in “jellies” with gas without causing shrinkage with Charles Learned which resulted in the invention of aerogel.
The Properties & Applications of Aerogel
The best-known and most significant importance of aerogel is its prodigious lightness, as it has the lowest density of any known solid- with a density of nearly 0.1 g/cm3, making it seven times less dense than even air.
The list of its properties continues surprisingly as aerogel is known to be as strong as steel and has a low thermal conductivity which in fact makes it a good insulator. Furthermore, they are hydrophilic, and thus if they absorb wetness, they go through a structural change making them hydrophobic; but this kind of degradation can be prevented through chemical treatments.
The most common use of aerogel is in the space industry, mostly NASA in spacesuits, obviously because of its weight and insulation capacity. The applications go further such as molten metals, waste management, optics and mild guides, digital devices, capacitors, imaging devices, catalysts, pesticides, and cosmic dust collection.
The Disadvantages of Aerogel
Many aerogels are utilized in the construction of houses as insulators. The majority of these insulators are environmentally beneficial, as they are 100% recyclable, do not include any ozone-depleting compounds, and are made up of 30% recycled content. There isn’t much waste in an aerogel because it’s mostly made up of air (90–94 percent). However, other aerogels with added ingredients for the increase in strength purposes can only be disposed of in landfills, which may cause severe environmental issues. Therefore, because of the chemical makeup of the aerogel, others must be disposed of in hazardous waste facilities. The majority of aerogels are non-toxic and environmentally friendly. Aerogels will decompose in the environment into the sand, a common substance.
Overall, with having relatively fewer hazards to the environment, and multiple advantages throughout its usage, aerogel should be our favourite lightest solid so far!
Works Cited
https://www.nasa.gov/topics/technology/features/aerogels.html
https://www.hindawi.com/journals/jnm/2010/409310/
https://www.pheneovate.com/news-notes/2018/6/10/graphene-aerogel
