Effect of pH Value on Structural and Optical Properties of Transparent Nano-Crystalline TiO₂ Films Prepared by Sol-Gel Dip-Drive Coating

Abstract:

Thin films of TiO2 have been deposited on well cleaned glass substrates by Sol-Gel dip-drive coating technique. The films have been prepared at three different pH values (1, 3.5 & 9) of Sol and annealed in muffle furnace at 550°C for one hour and are allowed to cool to room temperature. The films were characterized by XRD, EDAX, SEM and UV-Vis Spectrophotometer. The as deposited films were found to be amorphous in nature. The annealed films exhibit anatase in crystalline structure. The EDAX results have shown that all the films are maintained with TiO2 in composition. The XRD results reveal that they are nano-crystalline in nature and the crystalline nature increases with pH of the Sol. The transmittance and absorbance spectra have shown that the films are transparent and band gap of the films are of the order of 3.2eV. The ab initio studies of TiO2 (using GGA) was performed with Vienna ab initio Simulation package and the band structure and effective masses of the electrons and holes were determined.

• Periodical: Advanced Materials Research (Volume 678)
• Pages: 80-85
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.678.80
• Online since: March 2013
• Authors: Krishnasamy Sakthivel, T. Venkatachalam
• Keywords: Ab Initio Study, Band Structure, Bandgap, Effective Mass Holes, Effective Mass of Electrons, Sol-Gel Dip-Drive Coating, TiO₂

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