Formation of Transparent Nanoporous Titanium Oxide Films on Glass Substrates Using an Anodization Process

Abstract:

We report on an experimental study on transparent nanoporous titanium oxide films on glass substrates using an anodization process. Ti thin films of 50-90 nm have been deposited on glass substrate by dc sputtering (1.8210-3 Pa, 100 W) followed by a thermal treatment of 500°C for 30 min. in order to improve the adhesion to the glass substrate. Then an anodization process was applied in order to obtain TiO2 thin nanoporous layers using a cell consisted of three electrodes and aqueous electrolyte solution of 1% NH4F concentration, monoethyleneglycol and DI water. After anodization the samples were annealed at 450°C for 45 min using nitrogen gas. The layers have a nanoporous structure with pore dimensions in the range of 50-80 nm. FTIR and micro-Raman spectroscopy were used to identify the crystalline phase of the TiO2 layers. Raman scattering spectra clearly identify the anatase phase on the basis of Eg modes at ~ 146 cm-1 of the TiO2. The FTIR spectrum showed only the peak at 614 cm−1 which can be associated with the characteristic vibrational mode of TiO2 anatase. The optical properties of TiO2 thin films have been determined by ellipsometric measurements in the spectral range (0.2-0.8 μm) and a value of 2.41-2.45 was obtain for refractive index at 632 nm. Spectrophotometric measurements showed a transmittance over 70% and an optical band gap of 3.3-3.5 eV was determined.

• Periodical: Journal of Nano Research (Volume 16)
• Pages: 113-118
• DOI: https://doi.org/10.4028/www.scientific.net/JNanoR.16.113
• Online since: January 2012
• Authors: Elena Manea, Cosmin Obreja, Munizer Purica, Adrian Dinescu, Florin Comanescu, Vasilica Schiopu, Elena Budianu
• Keywords: Anatase, Anodic Oxidation, Magnetron Sputtering, Nanoporous Films, Titanium Oxide

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