SiO2 aerogels prepared by ambient pressure drying with ternary azeotropes as components of pore fluid

• In the paper, silica aerogels were prepared by ambient pressure technique, reducing preparing cost than supercritical drying technique.
• The test is concentrated on reducing the surface tension of pores to ease drying time and keep structure of pores with different solvents.
• The test has certain practical significance because of simple method and low risk. It is contribute to direct the preparation of other kinds of aerogels.
• The aerogels can be applied to insulation materials.

Silica aerogels were synthesized by two-step sol–gel polymerization of tetraethoxysilane (TEOS) in alcohol and using ambient pressure drying with ternary azeotropes as components of pore fluid. The structure and physical properties of these aerogels were investigated by several experimental methods, such as scanning electron microscopy (SEM), thermo-gravimetric and differential scanning calorimetry (TG–DSC), Fourier transform infrared spectroscopy (FTIR), specific surface area analyzer and pore size analyzer. The results indicated that silica aerogels are coherent, hydrophobic and nano-porous solid. The high specific surface was 838.6 m2/g.