PbS quantum dots-sensitized ZnO nanorods-based third generation solar cells

Abstract

PbS quantum dots (QDs) and PbS QDs-sensitized ZnO nanostructures of rod-like shape have been synthesized by the successive ionic layer adsorption and reaction method. The optical absorption spectra PbS QDs indicate that the prepared sample exhibits significant visible light absorption. The light absorption of PbS QDs-sensitized ZnO nanorods (NRs) was higher than bare ZnO NRs. X-ray diffraction pattern of PbS QDs exhibits diffraction peaks corresponding to (200), (112), and (202) planes of PbS. A Uniform development of ZnO nanostructures of rod-like shape and the PbS QDs deposition over its surface was witnessed from the field-emission scanning electron microscope and transmission electron microscope images. The small ring pattern confirming the polycrystalline nature of the prepared PbS thin film was observed from the selected area electron diffraction pattern. Solar cells were made using PbS QDs-sensitized ZnO NRs as photoanodes and it exhibited a power conversion efficiency of 1.2%.