The control of the diameter of the nanorods prepared by dc reactive magnetron sputtering and the applications for DSSC

Abstract

The TiO2 nanorod arrays, with about 1.8 μm lengths, have been deposited on ITO substrates by dc reactive magnetron sputtering at different target-substrate distances. The average diameter of these nanorods can be modified from about 45 nm to 85 nm by adjusting the target-substrate distance from 90 mm to 50 mm. These nanorods are highly ordered and perpendicular to the substrate. Both XRD and Raman measurements show that the nanorods prepared at different target-substrate distances have only an anatase TiO2 phase. The nanorods prepared at the target-substrate distance less than 80 mm have a preferred orientation along the (220) direction. However, this preferred orientation disappears as the target-substrate distance is more than 80 mm. These TiO2 nanorods have been used as the electrodes for dye-sensitized solar cells (DSSC). The highest conversion efficiency, about 4.78%, has been achieved for TiO2 nanorods prepared at 80 mm target-substrate distance.