Preparation and characterization of low-density Cu-doped SiO₂ composite aerogels

The Cu-doped SiO2 composite aerogels with different Cu doping content were successfully prepared by sol-gel process and subsequently supercritical drying with carbon dioxide. Tetramethyl orthosilicate and copper (Ⅱ) acetate were used as Si source and Cu source, respectively. The structures and properties of the composite aerogels were characterized by FTIR, SEM, EDS, BET and DMA. With the increase of the content of copper, the density of the composite aerogels increased and the specific surface area decreased. All of the samples processed a structure of 3-D network, low density (less than 40 mg/cm3), high specific surface area (more than 390 m2/g) and fine formability.