Aerogel. Close-up of a flower on a piece of aerogel being heated by a Bunsen burner, illustrating the insulating properties of the gel. Aerogel, or fr

Aerogel. Close-up of a flower on a piece of aerogel being heated by a Bunsen burner, illustrating the insulating properties of the gel. Aerogel, or frozen smoke, is a synthetic silicon-based material derived from a gel, in which the liquid component of the gel has been replaced with a gas. It is 1000 times less dense than glass and 39 times more insulating to heat than fibreglass. It is used as building insulation in walls and windows, thus improving energy efficiency. Other possible uses include acoustics, battery technology and microelectronics.