An investigation on the photovoltaic properties of dye-sensitized solar cell based on titanium dioxide — Reduced graphene oxide composite photoelectrode under low illumination

Abstract

The dye-sensitized solar cell (DSSC) is a promising device due to indoor application. However, there are fewer literatures to discuss why photovoltaic performances of DSSC can be enhanced under low illumination. In this study, we investigated the photovoltaic performances of DSSC based on titanium dioxide (TiO 2 ) — reduced graphene oxide (RGO) composite photoelectrode under the low illumination. Moreover, the composite of TiO 2 and RGO is synthesized by hydro-thermal method. Besides, the photoelectrode of DSSC is fabricated by a simple process of spin coating. According to experimental results, the photovoltaic conversion efficiency increases slowly during decreases in illumination, but which falls sharply at the lowest illumination. Furthermore, the photovoltaic conversion efficiency is enhanced from 4.01% to 4.91% under low illumanation. According to experimental results, the reason of increase in photovoltaic conversion efficiency of DSSC under low illumination is due to the improvement of electron injection quantum yield. Moreover, the reason of increase in photovoltaic conversion efficiency is clarified.