Loading...

TiO2 nanostructured films on mica using liquid phase deposition

Pourmand, M ; Sharif University of Technology | 2008

396 Viewed
  1. Type of Document: Article
  2. DOI: 10.1016/j.matchemphys.2007.08.011
  3. Publisher: 2008
  4. Abstract:
  5. Liquid phase deposition is a method to grow conformal TiO2 films with good crystallinity on various substrates. The growth depends on the hydrophilicity of the substrate surface and we found that mica is a substrate capable of forming uniform and thick films. Films were grown using an aqueous solution of TiF4 through a hydrolysis-condensation process. We have studied films properties; morphology, porosity and thickness, in terms of growth conditions, i.e. TiF4 concentration, growth temperature, deposition time and pH. The porosity of films was shown to rapidly increase from about 18% to about 25% and remained the same for longer growth times. The growth process of films could be identified by three stages; the initial delay, the fast growth and finally growth saturation. The fast growth showed a first order kinetics and resulted in 0.086 eV activation energy that was attributed to Ti-F hydrolysis reaction. The growth saturation was at a mass thickness of about 500 nm and for low-temperature solutions could not be reached even after 70 h. We observed also a dynamic pH change during the growth, and attributed the saturation of growth to the drop of pH to values where growth speed is negligible. © 2007 Elsevier B.V. All rights reserved
  6. Keywords:
  7. Activation energy ; Deposition ; Film growth ; Hydrolysis ; Mica ; Nanostructured materials ; Thick films ; Titanium dioxide ; Dynamic pH change ; Hydrolysis condensation process ; Liquid phase deposition ; Oxide films
  8. Source: Materials Chemistry and Physics ; Volume 107, Issue 2-3 , 2008 , Pages 449-455 ; 02540584 (ISSN)
  9. URL: https://www.sciencedirect.com/science/article/abs/pii/S0254058407005135