![]() 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 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. Additionally, the chemical composition of the composite gels was determined using FTIR, Raman, XRD and XPS. 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. ![]() The potential of GO to act as a nanofiller, for ambient pressure dried, hydrophobic silica aerogels, was systematically investigated. 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 resulting aerogel monoliths have a well-developed mesoporous structure (mean pore size of ∼15nm) with low density (∼0.13g/cm3) and a high specific surface area (∼730m2/g). Finally, most of the wet monolith samples were successfully transformed to aerogel monoliths without visible cracks. Surface-modified gel monoliths were carefully dried at atmospheric pressure and were then transformed to aerogels by the ‘springback’ effect during the drying process. silylation) of the gel surface was controlled using trimethylchlorosilane with isopropyl alcohol. After gelation and aging, the pore liquid (H2O) of silica hydrogel was sequentially exchanged with n-Hexane by multiple solvent exchanges using acetone as an intermediate exchanging solvent. ![]() Aqueous colloidal silica hydrosol obtained from the ion-exchange of an industrial waterglass was used as an inexpensive stating material. ![]() For the successful preparation of crack-free silica aerogel monoliths (disk and tile) at ambient pressure, the effect of surface modification conditions on the hydrophobicity of aerogels was investigated. ![]()
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