Comparison of low crystallinity TiO2 film with nanocrystalline anatase film for dye-sensitized solar cells.

Dye adsorption and microstructure of TiO2 film are important properties when it is used as photoelectrode of dye-sensitized solar cells (DSCs). This study investigated the application of a low crystallinity TiO2 film in DSCs. The low crystallinity TiO2 film is composed of interconnected spherical particles with an average size of 20 nm and has homogeneous mesoporous inner structure. A DSC based on the anatase nanocrystalline mesoporous film prepared by P25 was used for comparison purpose. It is shown that although loaded with much less dye, the DSC based on the low crystallinity TiO2 film generated Isc (short circuit photocurrent) as much as the one based on the conventional anatase nanocrystalline film does and obtained higher Voc (open circuit photovoltage) as well as ff (fill factor). The overall light-to-electricity efficiency (η) of the DSC based on the low crystallinity TiO2 film reached 5.37%, while the η of the DSC based on anatase nanocrystalline film was 4.69% in this work condition. It is suggested that a low crystallinity TiO2 mesoporous film with a proper microstructure is as efficient as the anatase nanocrystalline mesoporous film when used in DSCs.