Paper Title
Photovoltaic Parameters and Charge Transfer Properties of Dye-Sensitized Solar Cells based on Tio2 Nanotubes/Nanoparticles

Abstract
The application of Titanium dioxide based devices is mainly dependent on their morphology and size. In this study, two kinds of TiO2 powder with different structures namely nanoparticles (TNPs) and nanotubes (TNTs) have been prepared by sol-gel synthesis using titanium tetraisopropoxide (TTIP) as precursor and hydrothermal synthesis using commercial P25 powder (~20 nm particle size), respectively. The structures and the morphologies of both TiO2 nanotubes and nanoparticles were characterized using XRD, SEM and TEM/HRTEM. The titania nanotubes are 7.4 nm width while the nanoparticles size are in the range of 10-20nm, bothgrown inanatase phase. TiO2-based photoanodeswere fabricatedby combining nanotubes and nanoparticles with various ratios. The DSSCs wereassembled using N719 dye as photo sensitizer, platinum thin film as counter electrode anda iodide liquid electrolyte.I(V) and EIS measurements were recorded under illumination. The results are promising for the fabrication of low-cost DSSC with high power conversion efficiency. Keywords: TiO2, Nanoparticles, Nanotubes, Dye-Sensitized Solar Cells, EIS