Effect of doping on ZnO based transparent conducting oxides and down/up conversion phosphor for solar cell application

Abstract

Paper presented to the 3rd Southern African Solar Energy Conference, South Africa, 11-13 May, 2015.Boron doped ZnO (ZnO:B) films were grown by the spin coating method. The structure of the ZnO:B film has been found to exhibit the hexagonal wurtzite structure. A minimum resistivity was obtained to be 7.9×10-4 Ω-cm at 0.6 at.% of B concentration in the ZnO:B films. The optical interference pattern in the transmittance spectra shows good homogeneity with a transparency of ~91%, in the visible region. The efficiencies of the dye sensitized solar cell (DSSCs) formed using the ZnO:B window layers were obtained to be 1.56 %. Rare earth doped oxide based nano-phosphors for up and down conversion applications were also synthesised by a solution combustion method. The efficiency of the DSSC can be enhanced by using an extra layer of down and up conversion phosphor material as a layer on top of the solar cell.