Investigation on the performance of nanostructure TiO2 bi-layer as photoanode for dye sensitized solar cell application

Abstract

The photoanodes in dye-sensitized solar cells with two different morphologies such as one dimensional hydrothermally synthesized rutile nanorods and nanoparticles of TiO2 were utilized for improving the short circuit current density of the device. The synergistic effect of both the structures offer high Jsc by providing better pathway for the electron transportation through one dimensional nanorod morphology and efficient light absorption due to more dye adsorption on the mesoporous nanoparticles.With this, the condensation reaction mechanism for the formation of TiO2 rutile nanorod structure is elucidated along with FESEM analysis. The Field Emission Scanning Electron Microscope images confer the presence of highly oriented and vertically aligned nanorods. X-Ray Diffraction and RAMAN Spectroscopic studies confirm the crystalline nature of synthesized bi-layer film and it was observed to be a mixture of anatase and rutile phase of TiO2. The absorption and emission properties for the synthesized samples were studied using UV–Vis and Photoluminescence spectroscopy. The efficiency of the solar cells with the photo anodes of Nanorods, Nanoparticles and Nanorods/Nanoparticles bi-layer were found to be 0.30%, 4.41% and 4.23% respectively. Electrochemical Impedance Spectroscopic studies have done to check the charge transfer properties of the fabricated devices.