Effect of TiO 2 nanotube length and lateral tubular spacing on photovoltaic properties of back illuminated dye sensitized solar cell

Abstract

The main objective of this study is to show the effect of TiO 2 nanotube length, diameter and intertubular lateral spacings on the performance of back illuminated dye sensitized solar cells (DSSCs). The present study shows that processing short TiO 2 nanotubes with good lateral spacings could significantly improve the performance of back illuminated DSSCs. Vertically aligned, uniform sized diameter TiO 2 nanotube arrays of different tube lengths have been fabricated on Ti plates by a controlled anodization technique at different times of 24, 36, 48 and 72 h using ethylene glycol and ammonium fluoride as an electrolyte medium. Scanning electron microscopy (SEM) showed formation of nanotube arrays spread uniformly over a large area. X-ray diffraction (XRD) of TiO 2 nanotube layer revealed the presence of crystalline anatase phases. By employing the TiO 2 nanotube array anodized at 24 h showing a diameter ̃80 nm and length ̃1·5 μm as the photo-anode for back illuminated DSSCs, a full-sun conversion efficiency (η) of 3·5%was achieved, the highest value reported for this length of nanotubes. © Indian Academy of Sciences.