An efficient and low-cost TiO2 compact layer for performance improvement of dye-sensitized solar cells

Abstract

A TiO2 org. sol was synthesized for the prepn. of a compact TiO2 layer on fluorine-doped tin oxide (FTO) glass by a dip-coating technique. The resultant thin film was used for the fabrication of dye-sensitized solar cells (DSSCs). The compact layer typically has a thickness of ca. 110 nm as indicated by its SEM, and consists of anatase as confirmed by the XRD pattern. Compared with the traditional DSSCs without this compact layer, the solar energy-to-electricity conversion efficiency, short-circuit current and open-circuit potential of the DSSCs with the compact layer were improved by 33.3%, 20.3%, and 10.2%, resp. This can be attributed to the merits brought by the compact layer. It can effectively improve adherence of TiO2 to FTO surface, provide a larger TiO2/FTO contact area, and reduce the electron recombination by blocking the direct contact between the redox electrolyte and the conductive FTO surface.