Effect of Iodine Concentration in the Quasi-Solid State Electrolyte on the Photovoltaic Performance of Dye-Sensitized Solar Cells

Abstract

In the present study, the effect of iodine concentration on the photovoltaic properties of dye sensitized solar cells (DSSCs) based on the quasi-solid state electrolyte has been investigated. The electron transport properties and interfacial recombination kinetics have been evaluated by electrochemical impedance spectroscopy (EIS). It is found that increasing the concentration of iodine decreases the open-circuit voltage (Voc) whereas short circuit current density (Jsc) and fill factor (FF) shows improvement. The increment in Jsc for 0.05 M I₂ concentration is ascribed to the decreased charge transfer resistance value obtained by EIS analysis. In addition increasing the concentration of I₂ decreases the Voc which is attributed to the increased recombination with tri-iodide ions (I₃⁻) as verified from the EIS analysis under dark condition.

Keywords:

• Dye-sensitized solar cells
• iodide/triiodide
• photovoltage
• exchange photocurrentdensity
• photovoltaic performance

Acknowledgment

This work was supported by the 2014 Yeungnam University Research Grant.