Initial performance of dye solar cells on stainless steel substrates

The suitability of stainless steel for dye solar cell substrate was investigated with respect to performance and stability using photovoltaic characterization, electrochemical impedance spectroscopy (EIS), open circuit voltage decay (OCVD), and substrate polarization measurements. Stainless steel was employed both as photoelectrode and as counter electrode substrate gaining initial cell efficiencies of 4.7% and 3.5%, respectively. The leakage current from the stainless steel substrate was found to be very low. The effect of the stainless steel substrate on the performance of the other cell components was also examined. The traditional data analysis based on external cell voltage was shown to be inadequate and even misleading. Here, the voltage over a single cell component was determined computationally on the basis of EIS measurements as a function of cell current; through this approach, we found that the stainless steel counter electrode did not have any impact on the photoelectrode whereas the stainless steel photoelectrode substrate decreased the effective electron lifetime and the recombination resistance of the dyed TiO2 film.