Eosin-Y Sensitized Bi-layered ZnO Nanoflower-CeO2 Photoanode for Dye-Sensitized Solar Cells Application
Abstract
The energy demand is increasing with the development of science and technology, as even common people are accessible to use different home appliances, devices, and gadgets. Solar energy could be the only feasible solution to the present and future energy crisis. Amongst different types of solar cells, dye-sensitized solar cells (DSSCs) can cope up with the situation by providing a cost effective and environmentally suitable solution. In the present work, Eosin-Y sensitized bi-layered ZnO nanoflower-CeO2 photoanode was synthesized for DSSCs. The compact ZnO nanoflower-CeO2 layers were deposited by dip coatings and doctor blade methods, respectively. From the X-ray powder diffraction (XRD) analyses, the structures of both ZnO and CeO2 were confirmed with the nanocrystalline size of ~15 and ~10 nm, respectively by the Scherrer formula. Scanning electron microscope (SEM) confirmed the nanoflower morphology for ZnO (useful in dye adsorption and electron transfer) and porous, rough and spongy morphology for CeO2 (useful for dye adsorption). The band gap values of ~3.2 and ~3.1 eV for ZnO and CeO2, respectively, were calculated using UV-Visible data by the Tauc’s plot. After the device fabrication, from the J-V characteristics, the solar cell parameters for best-performing cells were calculated as open-circuit voltage ~460 mV, short circuit photocurrent density ~0.4m A/cm2 with a fill factor of ~55%.
