Effects of CdS-TiO₂ Working Electrode Layer on Dye Sensitized Solar Cell Investigated by Impedance Spectroscopy

Abstract:

The efficiency of dye-sensitized solar cell (DSSC) has been improved by various ways. In this work, The CdS nanoparticles were added in the TiO₂ working electrode for improving the efficiency of DSSC. The DSSC structure comprises of TiO₂ working electrode with and without CdS powder, Pt counter electrode, rutherium (II) (N719) dye and lithium iodide electrolyte. Normally, the TiO₂ paste was screened for five layers. In this work, the TiO₂ paste with CdS nanoparticles was screened for various numbers of layers on the layers of pure TiO₂ to get the total of five layers. Then TiO₂ mixed and unmixed CdS nanoparticles and Pt films were annealed at the temperature of 500°C for 50 min. Impedance spectroscopy (IS) was used to study charge transport in each interface of DSSC. For illumination condition, the measured IS can be divided into three regions that were charge transport at Pt layer, charge transport at working electrode/dye/electrolyte interface and ion contribution at electrolyte layer. The carrier transport parameters extracted from fitting IS spectra were chemical capacitance, charge transfer resistance and time constant.

• Periodical: Key Engineering Materials (Volumes 675-676)
• Pages: 101-104
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.675-676.101
• Online since: January 2016
• Authors: Prathan Prachopchok*, Janesuk Potisart, Chanu Photiphitak, Tossapol Tippo
• Keywords: CdS Nanoparticles, Dye-Sensitized Solar Cell

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