Construction of Solid-State Thin Film Solar Cell by Applying Visible Light-Responsive TiO2 Thin Film Materials

Abstract

A radio frequency magnetron sputtering (RF-MS) deposition method was employed to prepare visible light-responsive TiO 2 thin films (Vis-TiO 2 ) which can absorb visible light above 400 nm and be applied as a working electrode for sandwich-type two-electrode dye-sensitized solar cells (DSSCs). The effects of Cu 2 O and CuI deposition on the photovoltaic cell performance of these Vis-TiO 2 / ITO-glass electrodes were also investigated. The Cu 2 O/Vis-TiO 2 /ITO-glass electrode exhibited higher photovoltaic cell performance than that without Cu 2 O deposition, showing that electron injection from the photoexcited Cu 2 O into the conduction band of the Vis-TiO 2 thin film plays an important role in increasing the photovoltaic cell performance. Furthermore, it was found that the deposition of CuI as well as the UV-TiO 2 thin film was also effective in enhancing the photovoltaic cell performance of the Vis-TiO 2 /ITO-glass electrode. To construct solar cells using solid electrolytes, the gelation of a NaI/I 2 redox electrolyte was investigated using poly(acrylic acid) partial potassium salt. Finally, it was demonstrated that a DSSC system applying Vis-TiO 2 /N719/CuI/Au is a promising candidate in the development of unique all solid-type DSSC systems.