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Two 10 and 20nm samples of Cu nano-cluster were grown on quartz substrates with a thickness of by electron beam deposition method. Nanolayers of titanium dioxide with a thickness of 300 nm were deposited on these Cu nano-cluster layers. For comparison، a layer of titanium dioxide with a thickness of 300 nm was also coated on quartz substrate. All coatings were conducted using electron-beam physical vapor deposition. The effect of Cu nano- cluster thickness on the surface morphology، grain size، grain boundaries، crystalline structure and phases, and optical properties of titanium dioxide layers were studied. The Field Emission Scanning Electron Microscope (FESEM) was used to analyze the surface morphology of prepared layers. Moreover, the crystalline structure of layers and phase transitions on heat treatment were studied using X-Ray Diffraction (XRD). The UV-Visible spectroscopy was used to analyze of the absorption and transmission spectra of titanium dioxide layers. Presence of Cu nano-cluster layers as sublayer increases surface roughness of the obtained TiO₂ layers and facilitates the phase transformation TiO₂ from anatase to rutile. Furthermore, presence of Cu nano-cluster sublayer decreases TiO₂ band gap energy for visible light absorption.

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In this research, titanium dioxide (TiO₂), as a metal-oxide semiconductor that can be applied in dye-sensitized solar cells as a photoanode, was studied and synthesized. For this reason, thin films of TiO₂ were grown using the spray pyrolysis method and their physical properties were studied. To prepare the FTO substrate as the conductive layer, the FTO layer was deposited on the glass substrate. The transmittance above 90% in the visible region and low electrical resistance allows the use of the synthesized FTO as a transparent electrode. Subsequently, TiO₂ films were coated using spray pyrolysis at the temperature of 150°C on top of both bare glass and FTO coated glass substrates. The precursor solution for spray was made of TTIP as the main material and isopropanol as solvent. Samples were prepared by two methods of pulsed and non-pulsed spraying in two volumes of precursor solution of 200 and 350 mL. Results showed that the pulsed deposited samples cause the formation of TiO₂ films with higher crystal quality. XRD pattern analysis revealed the formation of the anatase crystal phase with preferred growth along the (101) plane on the FTO substrate. Considering its physical characteristics, the TiO₂ sample deposited on FTO in a precursor solution volume of 200 mL by the pulsed method was introduced as the most suitable sample for being used as a photoanode.
 

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The aim of this study was to fabricate nanocomposites of titanium dioxide nanorods/gadolinium oxide and to investigate some of their properties. So, in this research, titanium dioxide (TiO₂) nanorods were fabricated by microwave methods. The properties of crystal structure, morphology, optical, hydrophilicity and hydrophobicity of the samples were investigated. Nanocomposites of  5, 10, 15 and 20 percent of gadolinium oxide (Gd₂O₃) were fabricated using titanium dioxide nanorods. The properties of the fabricated samples, such as crystal structure and morphology, were investigated by X-ray diffraction, scanning electron microscopy, and energy-dispersive x-ray spectroscopy, respectively. The results of experiments showed that titanium dioxide nanorod have a rutile phase with tetragonal crystal structure. The contact angle and visible-ultraviolet spectroscopy of the samples were also studied. Layer samples were made from titanium dioxide nanorods, gadolinium oxide (Gd₂O₃) and also various nanocomposites by spin coating method. The contact angle of titanium dioxide nanorods was about 44 degrees, indicating the hydrophilicity of titanium dioxide nanorods. Also, the results showed that nanocomposites samples with TiO₂ nanorods reduce the hydrophilicity. The optical gap of titanium dioxide nanorods was about 2.9 eV. The optical energy gap of nanocomposite samples with different percentages of gadolinium oxide was almost constant.