Table 1: Precursors for silica aerogel synthesis.

Hydrophilic precursorsHydrophobic precursors

Tetramethoxysilane (TMOS)Methyltrimethoxysilane
Tetraethoxysilane (TEOS)Methyltriethoxysilane (MTES)
Sodium Silicate (Na2SiO3)
(i) Aerogels- high optical transmission ( > 90 %). (i) Aerogels-opaque.
(ii) Density < 0.1 g/cm3.(ii) Density > 0.1 g/cm3.
(iii) Hard & Brittle. (iii) Soft and flexible.