Analyses of the output characteristics and the internal impedance of dye-sensitized solar cell according to the fabrication of the blocking layer

DSCs are based on a dye-adsorbed porous TiO₂ layer as a photo electrode [1]. Under the illumination, dye molecules are excited and electrons are produced. The injected electrons in the conduction band of TiO₂ may recombine with the electrolyte. To obtain high performance DSCs, it is essential to retard the recombination. The charge recombination can be reduced by forming core-shell structure. In this work, we investigated the core-shell structure with Al₂O₃ and MgO coating layer on the porous TiO₂ layer. We confirmed the photovoltaic properties by I-V characteristics. The current and the efficiency was improved. In addition to, Through decrease in the width of EIS arc, which is the sum of the interfacial charge transfer resistances of both electrodes, we can be indicated that the block effect.