Summary: | 碩士 === 國立虎尾科技大學 === 光電與材料科技研究所 === 99 === In this study, we used the electrochemical anodization to prepare TiO2 nanotubes arrays that were investigated by field emission scanning electron microscopy (FE-SEM), X-ray Diffraction (XRD), UV-visible, I-V characteristics analyses and Electrochemical Impedance Spectroscopy (EIS). In the FE-SEM analysis, the lengths of TiO2 nanotubes arrays prepared by electrochemical anodization used Constant current method using the average growth per hour 4μm, can be obtained with approximately 10 μm, 20 μm and 30 μm. After TiCl4 treatment, the walls of TiO2 nanotubes were coated with TiO2 nanoparticles. XRD patterns can be found that the oxygen annealed TiO2 nanotubes have a better anatase phase. Preparation of counter Pt-electrodes by , transmittance in the visible range of 80 %. The conversion efficiency with different length of TiO2 nanotubes photoelectrodes are 3.21 %, 4.35 %, 4.34 % with 10 μm, 20 μm, 30 μm, respectively. After TiCl4 treatment, the efficiency of TiO2 nanotubes photoelectrode for dye sensitized solar cell can be improved to 6.58 %. In the electrochemical impedance spectroscopy (EIS) analysis, the value of Rk decreases with increasing the thickness of TiO2 thin films, the primary cause is related with the dye adsorptive capacity. It may be due to the stimulation of illumination for the electron in the dye, resulting in the reduced of the Rk.
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