Polymer electrolyte system based on Poly(3,4-ethylenedioxythiophene) (PEDOT) composites for dye-sensitized solar cells

• Main Author: Ng, Carlo Antonio T.
• Format: text
• Language: English
• Published: Animo Repository 2012
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/4313
• Institution: De La Salle University

Dye-sensitized solar cells (DSSC) are considered as possible next generation solar cells. Traditionally, DSSCs are fabricated with a liquid electrolyte solution. Due to the presence of the liquid electrolyte, the performance of the cell is limited due to leakage and evaporation of the liquid system, which hinders the practical use of DSSCs. The replacement of the liquid electrolyte system by solid polymer electrolytes has been successful in improving the long term stability of DSSCs. This study looks into the effect of utilizing a poly (3,4- ethylenedioxythiophene) (PEDOT) based polymer electrolyte as an alternative electrolyte system for DSSCs. PEDOT is one of the most conductive polymer electrolytes commercially used and its conductivity can be improved further by doping. -carrageenan was used as the dopant and effects of different concentrations of the polysaccharide were prepared. Conductivity was observed to improve with the addition of the higher molecular weight carrageenan due to its ability to trap excess water, while low molecular weight carrageenan with PEDOT decreases its conductivity due to its inefficient trapping of water in its matrix. The polymer blends were characterized through FT-IR, CV, conductivity, SEM and EDX analysis. The most conductive PEDOT-carrageenan blend was determined and was successfully utilized as the electrolyte system in DSSCs. Photovoltaic analysis De La Salle University 10 revealed a DSSC with low efficiency with the polymer electrolyte system. The low efficiency of the DSSC with the PEDOT-carrageenan electrolyte system was due to low ionic mobility of the polymer matrix, which limited the transport of electrons and the high resistance of the polymer system which results to internal loss of current.