Graphene oxide reinforced high surface area silica aerogels

Silica aerogel structures were intercalated with graphene oxide (GO) via the addition of GO to the colloidal silica sol and subsequent sol-gel polymerization. The potential of GO to act as a nanofiller, for ambient pressure dried, hydrophobic silica aerogels, was systematically investigated. The influences of 0 to 2 wt% GO loadings, on the physical properties of silica aerogels, were analysed by examining the bulk density, volume shrinkage (%), pore volume and surface area of the composite aerogels. Additionally, the chemical composition of the composite gels was determined using FTIR, Raman, XRD and XPS. The study revealed that a GO addition of as little as 0.5 wt% is capable of supporting the porous framework of silica aerogels and also enhancing the properties of the gels simultaneously. The additions of 0.5 wt% GO increased the surface area and pore volume of the aerogel from 390 to 700 m2/g and 0.59 to 0.99 cm3, respectively, and decreased aerogel density from 0.19 to 0.14 g/cm3. The investigation therefore revealed that intercalation of the silica aerogel matrix with small quantities of GO can inhibit volume shrinkage during drying without hindering the physical properties of silica aerogels.