Abstract
Anatase (TiO2) thin films were grown by non-aqueous sol-gel dip-coating using titanium (IV) n-butoxide as precursor and 1-butanol as solvent. High withdrawal speed of 4.7 mm/s in dip-coating resulted in defect free films of 100 nm average film thickness after subsequent heat treatments. According to scanning electron microscope and X-ray diffraction measurements, the films consisted of nanocrystalline anatase with 30 nm mean crystallite size. Refractive index n(λ) and extinction coefficient k(λ) were determined over the wavelength range from 200 to 1650 nm. The optical band gap of the film material was approximately 3.2 eV.
The results showed very similar optical characteristics to those that
are accomplished with chemically more reactive aqueous sol-gel
processes. Furthermore, it was found that in addition to porosity,
coordination number of Ti atoms to nearest oxygen neighbors is likely to
have a significant role in explaining differences of optical properties
between bulk anatase and thin film materials of the present work.
| Original language | English |
|---|---|
| Pages (from-to) | 5882-5886 |
| Number of pages | 5 |
| Journal | Thin Solid Films |
| Volume | 519 |
| Issue number | 18 |
| DOIs | |
| Publication status | Published - 2011 |
| MoE publication type | A1 Journal article-refereed |
Keywords
- anatase
- non-aqueous sol-gel
- optical properties
- thin film
- Titanium dioxide
- Wemple-DiDomenico model