Photovoltaic Performances of Yb Doped CdTe QDs Sensitized TiO2 Photoanodes for Solar cell Applications

In this work, Yb doped CdTe QDs sensitized TiO2 photoanodes were fabricated for quantum dots sensitized solar cells (QDSSC) and their photovoltaic response were studied. Pure CdTe QDs and Yb doped CdTe QDs were prepared in aqueous phase by using mercaptosuccinic acid as a capping agent. The influence of dopant material on structural properties of CdTe QDs were studied by XRD analysis, which confirms that prepared QDs belongs to cubic zinc blende crystalline structure and the size of CdTe QDs were decreased with increasing dopant concentration. The dopant concentration dependent optical properties were studied by UV-vis absorption and fluorescence emission studies. Elemental composition of pure and Yb doped CdTe QDs were examined by EDX analysis and their formation were studied by XPS analysis. Capping of MSA molecules over CdTe QDs was confirmed by FT-IR analysis. Photovoltaic performance of pure and Yb doped CdTe QDs sensitized TiO2 photoanodes was studied by fabrication of QDSSC using polysulfide electrolyte. J-V characteristic curves reveal the enhanced solar cell efficiency of Yb doped CdTe QDs sensitized photoanodes.