Enhancement in absorption spectrum by ITO coated, down converting glass and increasing the SILAR cycles of PbS/CdS quantum dots sensitized ZnO nano with deposition of MoO3/Au/MoO3 (MAM) as a solid state solar cell

Abstract

This research describes the first-of-its-kind quantum dots sensitized solar cell (DC/ITO/ZnO/PbS/CdS/MoO3/Au/MoO3) that is efficient and economical. A down-converting (DC) transparent glass was prepared. One side of DC glass was coated with indium tin oxide (ITO) by sputter-coating technique to make it conductive for electric current. Zinc oxide (ZnO) nanorods were produced by the several steps of hydrothermal process. The PbS/CdS quantum dots (QDs) were then grown on top of ZnO nanorods by using a process known as Successive Ionic Layer Adsorption and Reaction (SILAR). The final layer for the back contact was deposited as a trilayer of (MoO3/Au/MoO3).Spin coating was employed in the process of depositing MoO3 layers, while thermal evaporation was used in the process of depositing the intermediate layer of gold (Au). For the deposition of (CdS/PbS) quantum dots with different number of SILAR cycles (10, 15 and 20) were employed. Afterwards MoO3/Au/MoO3 trilayer was deposited on the quantum dots (CdS/PbS) attached with the nanorods ZnO for the complete fabrication of three devices. As compared to the other quantum dots sensitized solar cell (QDSSC), it can absorb light from both ends which produced the remarkable results. Surface morphology, elemental and structural analyses were employed by SEM, EDS and XRD methods. UV–Visible analysis was performed to identify the optical properties of the devices. Overall performances were calculated of the three different devices by their power conversion efficiencies. The highest efficiency among all three devices was 10% corresponding to the 15 SILAR cycles.