Self-Cleaning TiO₂ Nanofilms on FTO Glass: Influence of Electrophoretic Deposition and UV Irradiation Conditions

Abstract:

In this research, anatase TiO₂ nanoparticles were electrophoretically deposited on the FTO glass. This investigation was focused on the self-cleaning property of TiO₂ coatings and the effects of different parameters on this characteristic such as: applied voltages during electrophoretic depositions and durations of UV irradiation. Electrophoretic depositions of suspensions were performed in different voltages of 10, 30 and 60 V (for 10 s) at room temperature. TiO₂ coatings were sintered in 450°C for 1 hr. The phase transformation of TiO₂ films was considered using XRD. Morphology, average particle size and the thickness of TiO₂ films was analyzed using FESEM microscope. The photocatalytic activity of TiO₂ films was evaluated by the degradation of aqueous methyl orange (MO) under UV irradiation. The ultraviolet-visible spectrophotometer was used to record the changes of the adsorbancy of the MO solution. Hydrophilicity of TiO₂ films was determined by measuring contact angle of water droplet with the surface of TiO₂ films. Results represented that decomposition rate of MO solution by TiO₂ films enhances from 6.5% to 31% by increasing applied voltage of deposition from 10 to 60V and from 5% to 40% by increasing UV illumination duration from 1 to 5 hours. It was also observed that the contact angles of water droplet with the surface of TiO₂ films decrease from 34^o to 6.6^o by increasing applied voltage from 10 to 60V.

• Periodical: Journal of Nano Research (Volume 30)
• Pages: 39-49
• DOI: https://doi.org/10.4028/www.scientific.net/JNanoR.30.39
• Online since: March 2015
• Authors: Nazila Horandghadim, Mohammad Ghorbani*, Abolghasem Dolati
• Keywords: Electrophoretic, Hydrophilicity, Nanofilm, Photocatalytic, Self-Cleaning, TiO₂

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