Effect of Different Organic Dyes and their Impregnation Periods on Photovoltaic Performance of ZnO Based Dye Sensitized Solar Cells

Abstract

Light absorption in dye sensitized solar cells (DSSCs) depends significantly on the type of sensitizer and its impregnation period. Since dye plays a vital role to broaden the light absorbance of semiconductor photoanode towards the visible region of spectra. The present study reports the effect of two types of organic dyes namely N719 and N749 (black dye) as well as their impregnation periods of 12 h and 24 h, respectively, on the photovoltaic performance of zinc oxide based DSSCs. Zinc oxide photoanode films were deposited on indium tin oxide substrates by doctor blade technique. The DSSC impregnated with N719 dye for the period of 24 h exhibited the highest value of photon conversion efficiency. This happened as the photoanode film impregnated with N719 dye for 24 h exhibited the highest optical absorption in the UV region as well as in visible region of spectra. The solar cell impregnated with N719 dye for the period of 24 h performed with the highest short-circuit density (JSC) of 9.38 mA/cm 2 , fill factor (FF) of 0.50, open circuit voltage (VOC) of 0.71 V and conversion efficiency (η) of 3.32 %.