Photovoltaic and impedance spectroscopy analysis of p–n like junction for dye sensitized solar cell

A dye-sensitized solar cell based on nanostructure TiO2 and PCBM:P3HT blend was fabricated and the photovoltaic and impedance spectroscopy properties of the solar cell were investigated. The solar cell gives a short circuit current density of 0.75 mA/cm2 and an open circuit voltage of 0.60 V under AM1.5. The photovoltage of the solar cell was greatly enhanced by PCBM:P3HT blend. The capacitance–voltage, the conductance–voltage, the series resistances–voltage characteristics of the solar cell were measured in a wide range of frequency for the first time for DSSC applications. The capacitance–voltage shows a behavior from the positive to negative capacitance due to injection of electrons from the FTO electrode into TiO2. It is evaluated that the photovoltaic performance of the dye-sensitized solar cell can be improved using various organic semiconductors.