Low temperature layer purification by pulsed UV-irradiation for flexible dye sensitized solar cells

Abstract

The efficiency of dye sensitized solar cells (DSSCs) is strongly influenced by the quality of the front electrode. To remove dispersal additives and to enable sintering effects the TiO2 layer has to be heated up to 450°C for one hour. Nevertheless, for flexible DSSCs the process temperature is limited by the foil to about 150°C. Hence, a sintering of the particles is not possible and the cleaning effect is also declined, but both can be compensated with the development presented in this paper. This paper demonstrates that after 90 min of permanent intensive UV-irradiation nearly all additives are evaporated. Furthermore, to decrease the stress on the foil a pulsed UV-irradiation is performed and the pulse-pause-ratio optimized