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    • Keywords

       

      Silica aerogel; hydrophobic; thermal stability; out-gassing; nanoindentation; space application.

    • Abstract

       

      Transparent super-hydrophobic monolithic silica aerogels are prepared by the cost-effective ambient pressure drying. The drying of aerogel is performed at various temperatures ranging from 25 to 200$^{\circ}$C. Oxidation states of different silica aerogels are investigated by XPS which shows the presence of both SiO and SiO$_2$ phases. Thermal stability of hydrophobic aerogel is found as $\sim$320$^{\circ}$C investigated by TGA and DSC. The chemical bonds (i.e., $–$CH$_3$) responsible for the hydrophobic (WCA > 170$^{\circ}$) nature of synthesized silica aerogels are identified by FTIR. Further, out-gassingproperties of the silica aerogels have been investigated and they are found in limit for the space application. The highest hardness and Young’s modulus are measured by the nanoindentation technique for the aerogel dried at 120$^{\circ}$C which has higher density, while density decreases for the aerogel dried at 200$^{\circ}$C and the corresponding nanomechanical propertiesare found to be lowest as expected.

    • Author Affiliations

       

      MOHAMMED ADNAN HASAN1 ARJUN DEY1 A CARMEL MARY ESTHER1 2 PAYEL MAITI3 ANOOP KUMAR MUKHOPADHYAY4 A RAJENDRA1

      1. Thermal Systems Group, U.R. Rao Satellite Centre (formerly ISRO Satellite Centre), Bengaluru 560017, India
      2. Present Address: Institute of Materials Physics, University of Munster, Wilhelm-Klemm-Str. 10, 48149 Munster, Germany
      3. Advanced Mechanical and Materials Characterization Division, CSIR - Central Glass and Ceramic Research Institute, Jadavpur, Kolkata 700032, India
      4. Department of Physics, School of Basic Sciences, Faculty of Science, Manipal University Jaipur, Jaipur 303007, India
    • Dates

       
  • Bulletin of Materials Science | News

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