Stability of UV illuminated dye sensitized solar cells (DSC) studied by photoinduced absorption in the second range

In this work we present a method to test the stability of dye-sensitized solar cells (DSC) exposed to UV. Photoinduced Absorption (PIA) in the second range was applied to dyed- and undyed cells with a 405 nm probe laser. The pump source was a UV diode with an intensity of approximately 100 x the suns UV content. PIA was used to determine the influence of UV on the DSC cell for dyed and undyed cells. With this highly sensitive setup, we have shown the influence of H2O in the electrolyte, which causes faster triiodide depletion. We found that this method is very suitable to test the purity of electrolyte and, more generally, the DSC tolerance towards UV illumination. The method can be applied to optimize the device life time. A comparison to cells which have been aged in a UV chamber was made, where faster degradation of DSC cells with H2O in electrolyte was also observed.