Electrochemical Properties of Graphene/PEDOT:PSS Counter Electrode in Dye-sensitized Solar Cells

Abstract

The poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) and reduced graphene oxide (rGO)/PEDOT:PSS have been prepared by spin coating as counter electrodes (CEs) for dye-sensitized solar cells. The optimized 1wt% rGO was dispersed in a solution of PEDOT:PSS for the highest electrical conductivity. The cyclic voltammogram result shows that rGO/PEDOT:PSS CE has a good catalytic activity towards the I⁻/I₃⁻ redox couple compared to Pt CE and PEDOT:PSS CE. The rGO/PEDOT:PSS CE showed a high energy conversion efficiency of 5.1% accompanied by a fill factor of 0.68, which was comparable to those of the Pt CE (4.6%) and PEDOT:PSS (2.4%). Hence, the rGO/PEDOT:PSS is expected to replace the expensive Pt as a promising CE catalyst.

Keywords:

• PEDOT:PSS
• reduced graphene
• dye-sensitized solar cells
• impedance analysis
• counter electrode

Acknowledgments

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (2012R1A1A3010655).