Preparation of surface modification of silica aerogels in ambient pressure drying

Silica aerogels were made by sol-gel techniques using tetraethyoxysilane,followed by drying under(ambient) pressure.By using BET,XRD and TEM,the results show that the silica aerogels have a high inner surface area and amorphous.Laser granularity analyzer shows the average particle size of silica aerogels is less than 20 μm,which is mesoporous structure.The surface chemical modification was confirmed by the FTIR spectroscopy studies.The thermal stability of the hydrophobic aerogels was studied from 25 to 1 200 ℃.The hydrophobic nature of the aerogels could be maintained up to around 500 ℃.Water adsorption further indicates that it is superhydrophobic.