Effect of Doping Zinc Oxide and Titanium Oxide Cells with (Al, Cd, Co,Li and Mg) on Optical Properties and Efficiency

Abstract

In this work the optical properties of two group of samples were studied. In the first group Zinc Oxide was doped by ( Al ,Cd, Co, Li and Mg ). In the second group Titanium Oxide was doped by ( Al ,Cd, Co, Li and Mg ) also . The optical characteristics where investigated by using UV spectrophotometer and some computer programmers . The efficiency of the solar formed from this samples using ITO were found using light current and voltage .The study shows that the absorption peaks of the samples corresponds to the energy gaps . The solar cells efficiency increases as the energy gap decreases . For TiO2 doped with CdO4 ,CoO2 ,LiO2 , MgO2 and Al2O3 the beak absorptions are( 308 , 308,310, 300 and 510) nm respectively the corresponding energy gaps are ( 3.688 ,3.42 ,3.482,3.364 and 2.155) eV respectively which shows inverse relation with energy peaks .This agrees with theoretical relations . The Mefficiencies are (0.188, 0.247 ,0.452 ,0.478 and 0.569 ) % which are inversely related to the energy gap expect for Lithium due to the existence of other factors affecting the efficiency . For Zn O doped with CdO4 ,CoO2 ,LiO2 , MgO2 and Al2O3 the beak absorptions are( 290 , 300,302, 305 and 504) nm respectively and the corresponding energy gaps are ( 3.644 ,3.685 ,3.505,3.687 and 3.699) eV while the corresponding efficiencies are (0.205, 0.204 ,0.297 ,0.191 and 0.168 ) % . The same comments and relations holds for Titanium holds also for zinc oxide group including Lithium again. It is clear that the efficiencies of TiO2 samples are higher than that of ZnO . It was also found that the absorption coefficient and theeffeciency increases as the energy gap decreases . These results agrees with many previous studies and theoretical relations