Effect of Thickness on Catalytic Performance of Cu Doped TiO2 Thin Films

Abstract

Thickness plays a vital role in determining properties of thin films and its variation influences performance of the thin films remarkably. In this work, the impact of thickness on the structural, morphological and optical properties of Cu-TiO2 thin films have been investigated in detail. Copper doped Titanium dioxide thin films with different thickness (~1.89 to 2.44µm) were deposited on glass substrates by sol gel dip coating technique and were annealed at 500°C for 3 h. The annealed films were subjected to different characterization studies. The surface morphology and stoichiometry of the prepared films were characterized by Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray spectroscopy (EDX) respectively. The microstructural parameters such as crystallite size, dislocation density and micro strain of deposited films demonstrate notable variations with increased film thickness. The optical absorption of Cu-TiO2 thin films show shift towards long wavelength region depending upon thickness. The photocatalytic activity of the different layered thin films was also tested via the degradation of Methylene Blue (MB) and Methylene Orange (MO) dye solutions under visible irradiation. The threshold thickness for best catalytic efficiency was acquainted and reported.