The analysis of dye-sensitized solar cells modified by different contents of graphene via electrophoretic deposition

In this study, titanium dioxide (TiO₂) film of dye-sensitized solar cell (DSSC) was modified by different contents of graphene via electrophoretic deposition (EPD). The influences of different contents of graphene on the structures of TiO₂ film were observed. Due to the high conductivity of graphene, the quality of TiO₂ film becomes better and the photovoltaic conversion efficiency of DSSC increased. According to the result, the optimal photovoltaic conversion efficiency was 3.92% when the content of graphene was 1.5 mL. Furthermore, the impedance behavior and equivalent circuit of DSSC can be characterized by electrochemical impedance spectroscopy (EIS), which can make us understand the condition of electron transportation in DSSC.