Graphene oxide reinforced high surface area silica aerogels

Abstract

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 2wt% 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 0.5wt% is capable of supporting the porous framework of silica aerogels and also enhancing the properties of the gels simultaneously. The additions of 0.5wt% GO increased the surface area and pore volume of the aerogel from 390 to 700m2/g and 0.59 to 0.99cm3, respectively, and decreased aerogel density from 0.19 to 0.14g/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.