Chemical Physics Letters, Vol.585, 193-197, 2013
Electrochemical impedance spectroscopy of dye-sensitized solar cells with thermally degraded N719 loaded TiO2
Here, we have deliberately degraded N719 loaded TiO2 photoelectrodes (PEs) at elevated temperatures; for example, from 80 degrees C to 160 degrees C with a step of 40 degrees C and studied their influence on photovoltaic parameters of dye-sensitized solar cells (DSSCs). Electrochemical impedance spectroscopy (EIS) study shows that the thermal degraded PEs suffered from increased recombination as well as downward shift of TiO2 conduction band that eventually decreased photovoltage of the cells. In contrast, incident photon-to-current efficiency (IPCE) reveals that poor light harvesting, charge collection and dye regeneration efficiency were responsible for low photocurrent of the DSSCs with thermal degraded PEs. (C) 2013 Elsevier B. V. All rights reserved.