Dye stability of dye-sensitized solar cells with a conducting and a non-conducting electrode

¹ Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China
² CAS Key Laboratory of Energy Conversion Materials, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China

^a e-mail: eedewang@ustc.edu.cn

Received: 13 May 2012
Revised: 27 October 2012
Accepted: 3 December 2012
Published online: 25 January 2013

Abstract

Dye-sensitized solar cells with thin film TiO₂ electrodes were fabricated. The TiO₂ films were prepared on conducting and non-conducting glass substrates. A high-intensity laser was shining on the dye/TiO2 electrodes to excite the dyes and inject electrons to the conduction band of the TiO2 electrode. The dye degradation rate showed much difference for the dyes adsorbed on the TiO₂ films on conducting and non-conducting glass substrates. On non-conducting glass substrate the injected electrons gathered near where they were injected. This increased the local Fermi level of the TiO₂ conduction band and consequently the electron injection efficiency was decreased, leading to a relatively high degradation rate for the dyes when they were radiated by a high-intensity laser. The experimental results showed that dye stability is sensitive to the local electro-chemical environment.