Synthesis Of ZnO Nanorods/Nanotubes Arrays And The Application On Dye-Sensitised Solar Cells

With global attention in the field of renewable energy, dye-sensitised solar cells(DSSC) are widely researched by scientists around the world and important progresshas been made due to its advantages such as environmental friendly, economy andsimple fabrication. The photo-anode material selection and preparation is one of themost important aspects of the research. Because of the outstanding properties withhigh orientation, one-dimensional (1D) nanostructure oxide is particularly suited to beused as photo-anode. Zinc oxide (ZnO) has great potential on DSSC due to its naturecharacter. Especially, the electron mobility is an order of magnitude higher than thatof TiO2. Meanwhile, ZnO is a cheap and environmental friendly semiconductor,which can be fabricated to various morphology of1D nanostructures through avariety of methods. The electrodeposition method has smaller energy consumption,shorter period and less pollution. Therefore, fabrication of highy-oriented1D ZnOnanostructure arrays through electrochemical method and the application on DSSCbecome the research emphasis in this paper.The main contents of this thesis include：1. ZnO nanorods/nanotubes arrays were produced on conductive glass throughelectrochemical deposition method. To find out the influences of depositiontemperature, time, current, etc., we fabricated a lot of ZnO nanorods/nanotubes arrayswith different parameters. The obtained samples were characterized By scanningelectron microscope (SEM) and X-ray diffraction (XRD) methods.2. Annealed at450℃for30min, the performance of the photo-anode could besignificantly improved. After that, to find out a proper sensitised condition and dyes,we researched on the dyes N719and N3. Studies had found that sensitized with N719for2h ZnO photo-anode can reach the top performance. We use the optimalsensitised condition to study the different parameters of ZnO arrays photo-anode. Thenanorod photo-anode is better than nanotube. And in certain range, the longer the nanorod, the better the performance is.3. Combined photo-anode can obviously increase the efficiency. One kind istreated with tetrabutyl titanate. The other kind is ZnO nanostructure arrayscomposited with prepared TiO2sol and gel to get two kinds of other combinedphoto-anodes. Photo-anode1is the TiO2nanoparticles filled in the holes of nanotubes.The other is TiO2paste coated on the ZnO with Doctor Blade method. The mixedTiO2can significantly improve the performance of the cells due to the lessrecombination and higher surface area.