Comparative Study of ZnO/Fe2O3 Nanocomposite Sensitized with Natural Pigments for Dye Sensitized Solar Cell

Abstract

This thesis examine and compares the efficiency of DSSC sensitized with natural dye extracted from Euphorbia amygdaloides and opuntia Ficus indica plant and pure ZnO, ZnO-Fe 2 O 3 and pure Fe 2 O 3 nanocomposite. The study starts by selecting natural dyes that they have good absorption spectra in the visible range using the UV-Vis spectrophotometer the selected natural dyes were Euphorbia amygdaloides and opuntia Ficus indica. Nanocomposites semiconductor oxide starting from pure ZnO, 95%ZnO-5% Fe 2 O 3 , 90% ZnO-10% Fe 2 O 3 , 80% ZnO-20% Fe 2 O 3 , and pure Fe 2 O 3 were prepared using co-precipitation method. Then the prepared semiconductor oxide particle sizes were estimated using XRD. The estimated size of the prepared nanoparticles were ZnO =39.84nm, 95%ZnO-5% Fe 2 O 3 =23.22nm, 90% ZnO-10% Fe 2 O 3 =32.44nm, 80% ZnO-20% Fe 2 O 3 =38.38nm and pure Fe2O3=35.47nm. Finally dye sensitized solar cells (DSSCs) had been assembled and characterized from each dye extracted, Euphorbia amygdaloides. (Using Ethanol) and opuntia Ficus indica (using water) and the prepared semiconductor metallic oxide. The current density-voltage characteristics in the dark and under white light illumination and also IPCE under monochromatic illuminations have been studied. Solar energy conversion efficiency (η) of the as-synthesized semiconductors sensitized by the natural dye (Euphorbia amygdaloides. and opuntia Ficus indica) was obtained in the following order ZnO>80% ZnO-20% Fe 2 O 3 >95%ZnO-5% Fe 2 O 3 >90% ZnO-10% Fe 2 O 3 > Fe 2 O 3. From the ten devices assembled best device parameter was achieved by the ethanol extract of Euphorbia amygdaloides. and pure ZnO nanoparticle semiconductor. The result was JSC=0.3696mAcm-2, VOC =0.33V, FF = 0.31 and η=0.038.