Nanomaterial by Sol-Gel Method: Synthesis and Application

Figure 6

Synthesis steps of hydrophobic silica aerogels [135]. (a) Hydrosol Na₂SiO₃ solution + tartaric acid. (b) Hydrogel. (c) Aged hydrogel. (d) Salt free hydrogel. (e) Alcogel. (f) Modified gel. (g) Hydrophobic silica aerogel.