Blocking Layer Effect on Dye-Sensitized Solar Cells Assembled with TiO2 Nanorods Prepared by dc Reactive Magnetron Sputtering

Three different thickness dense TiO2 (150 nm, 300 nm and 450 nm respectively) films were deposited on ITO substrates by dc reactive magnetron sputtering technique. These dense TiO2 films were used as the blocking layers. After that, TiO2 nanorod films were deposited on these dense TiO2 films by same technique. Both the dense and nanorod TiO2 films have an anatase phase. The dense TiO2 films have an orientation along the [101] direction and the TiO2 nanorod films show a very strong orientation along the [110] direction. These TiO2 materials were sensitized by N719 dye and the DSSCs were assembled using them as photoelectrode. The effect of the blocking layer on the efficiency of the DSSCs is discussed. The DSSC assembled using TiO2 nanorod film with 300 nm thickness blocking layer shows a high efficiency of 2.07%.