Aerogels: a nano-Material srjc, Spring 2009 Engineering 45 Chelsea Devlin



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Aerogels: A Nano-Material SRJC, Spring 2009 Engineering 45

  • Chelsea Devlin

  • Misha Maydoney

  • Nazareth Tesfai


Aerogel Timeline



Aerogels Video



Common to all types

  • As high as 99.8% air contained in a solid structure

  • Three times the density of air

  • Able to hold over 2000 times its own weight4

  • 39 times more insulating than the best fiberglass insulation1

  • Cost as much as $300 in3



Carbon Aerogels

  • How are Aerogels made?

  • In general aerogels are made by two steps.

    • Formation of the wet gel
    • The drying of the wet gel to make aerogel 6
  • Different reactants and catalysts for different kinds

  • Can be made from Carbon nanotubes4



Carbon Aerogels

  • Carbon Aerogel Can be Used For

  • Super Capacitors having capacitance ranging as high as thousands of Farads4

  • High: purity, useable surface area and electrical conductivity

  • Solar energy collectors

  • Black only reflecting .3% radiation in the UV to IR range



Silica Aerogels

  • the most common and most extensively studied

  • holds 15 records in the Guinness World Book of Records including the lowest-density solid at 1 mg/cm3 and best insulator at 0.03mg/cm3

  • strongly absorbs infrared radiation



Silicon Aerogels can be used in …

  • the production of LEDs due to its low refractory index

  • circuits as a low dielectric thin film in circuits to prevent crosstalk

  • cleaning industrial wastewater because its adsorption and absorption captures organic compounds such as oil.



Alumina Aerogels

  • Alumina Aerogels are made with aluminum oxide

  • When doped with other metals the applications include use as catalyst, nickel-alumina aerogels are most common.

  • Used to capture stardust, when doped with gadolinium and terbium the aerogel fluoresces at the site of particle impact and this can be used to find the impact velocity of the particle. 4

  • Can decompose toxic substances, such as Sarin, that are deposited on a corrosive surface. When a fine powder of alumina aerogels are dispersed on a surface covered with a toxin a heterogeneous chemical reaction decomposes the toxin.



Aspen Aerogels



Optical Properties

  • Most are opaque to visible light

  • New research is being done in NASA’s “Vomit Comit” to create microgravity situation to elminate boyancy and convection to make pore size smaller7



In Summary

  • Aerogels:

  • Low density makes it extraordinary as thermal insulators, filters, and catalysts.

  • Can be made from and doped with many different materials

  • Nano-materials that are mostly made of air

  • Thank You!



References

  • 1. http://www.connectexpress.com/~ips/aerogel/faq.html

  • 2.http://www.absoluteastronomy.com/topics/Steven_Kistler

  • 3.http://www.scientificamerican.com/article.cfm?id=strange-but-true-gossamer

  • 4.http://portal.jce.ac.il/courses/nano/Nanomaterials%20Projects/Aerogel_ZS_JZ060616%20copy.pdf

  • 5. http://www.connectexpress.com/~ips/aerogel/faq.htm

  • 6. http://home.earthlink.net/~douglaspage/id18.html

  • 7. http://www.scientificamerican.com/article.cfm?id=strange-but-true-gossamer



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