Because TiO2 photoelectrodes cannot
be prepared by high-temperature sintering (E150 1C) in PDSCs,
the following limitations arise: (1) no multilayer-structured
TiO2 photoelectrodes can be produced, which is optically
disadvantageous, and (2) TiO2 photoelectrodes should be thin
films because TiO2 particles in TiO2 photoelectrodes exhibit low
conductivity