Effect of TiCl4 Treatment on Porous ZnO Photoelectrodes for Dye-sensitized Solar Cells

In this study, photoelectrodes composed of a porous layer of 100-nm ZnO particles are fabricated for use in dye-sensitized solar cells. The electrodes are immersed in an aqueous TiCl4 solution to coat them with a thin layer of TiO2 for preparation of ZnO–TiO2 core–shell electrodes. This simple treatment drastically improves the cell performance, resulting in the highest obtained efficiency of 3.91%. This efficiency is higher than that of 100-nm TiO2 particle cells.