Synthesis and Investigation on the Properties of Silica-Graphene Oxide Nanocomposite Coating

Afzali, Neda | 2016

442 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 48088 (07)
  4. University: Sharif University of Technology
  5. Department: Materials Science and Engineering
  6. Advisor(s): Dolati, Abolghasem
  7. Abstract:
  8. The investigations on hydrophobic surfaces have attracted lots of intrests in science and technology. Silica sols have been used extensively in the area of producing hydrophobic coatings. On the other hand, carbon-based materials have attracted of a great deal of scientific interest in recent years. The purpose of this research is synthesis and investigation on the properties of Silica- Graphene Oxide nanocomposite coating.Graphene Oxide synthesized by using Hummer’s method. Silica nanoparticles were prepared using sol-gel process and tetraethylorthosilicate (TEOS) as precursor. The surface hydroxyl groups of silica nanoparticles are replaced with Methyl groups by treatment with hexamethyldisilazane (HMDS) and dispersed Graphene Oxide sheets were added in order to improve electrical properties and adhesice performance of nanocomposite coating.Field Emission-Scanning Electron Microscopy (FE-SEM) for evaluating the morphology of coating, X-ray Photo Electron Spectroscopy (XPS) for chemical composition, Atomic Force Microscopy (AFM) for surface topography and roughness and Electrochemical Impedance Spectroscopy (EIS) for measuring electrical conductivity were used. For study of wettability properties, sessil drop method was applied. The results of this study showed that by increasing Graphene Oxide from 2.5 g/L to 12.5 g/L Contact Angle (CA) raised up from 23º to 94º. The use of Graphene Oxide to improve the wear resistenece is effective and causes wear resistence of silica coating increased from 2H to 6H measuring with pencil test. Heat treatment at 200ºC for around 2 hours caused impedance decrease from 7.1 kῼ to 5.5 kῼ. Based on researches and the results, synthesis of this coating is a new approach in the field of producing hydrophobic coatings
  9. Keywords:
  10. Graphene Oxide ; Silica ; Hydrophobicity ; Sol-Gel Method ; Antistatic Additive

 Digital Object List