Preparation of Hollow Titanium Dioxide Shell Thin Films by Electrophoresis and Electrolysis for Dye-Sensitized Solar Cells

Titanium oxide (TiOx) thin films were prepared by cathodic electrolysis of a solution of ammonium hexafluorotitanate and ammonium nitrate at 323 K on polystyrene (PS) spheres template adsorbed on a transparent conducting substrate [fluorine-doped tin oxide (FTO)] by electrophoresis. The calcination at 723 K converted the FTO/PS core/TiOx shell to a hollow anatase-type titanium dioxide (TiO2) thin film. The energy-conversion efficiency of a dye-sensitized solar cell per TiO2 weight using the hollow TiO2 shell electrode was higher than that with a nanoparticle-sintered electrode.