Supercritical Drying Autoclave Preparation of Zirconia Aerogel Nanostructures

Abstract

In this work, zirconium dioxide aerogel monoliths were successfully prepared using drying autoclave method. The effects of synthesis environment on the morphological, optical and thermal properties of the synthesized monoliths were studied. The implemented autoclave was able to produce aerogel monolith of surface area up to 998.25 g/m² and thermal conductivity of 0.0053 mW.m^-1.°C, associated with density of 0.047 g/cm³. It was found that the density, optical transmittance and porosity are strongly affected by the starting pH value as their final microstructures were introduced by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) method. The lack of catalyst during aerogel preparation has resulted in dense, opaque and less porosity monoliths. As the environment was little basified, the aerogel properties were remarkably varied, while acidifying the reaction setting had gradual influence on the final aerogel properties.