Preparation Of ZnO Nanomateriais And Appliation In Photoanode&Photocaialyst

It is a promising solution for sustainable development of the society that converts solar energy into electricity and chemical energy by using photo-generated charge separating effect of the semiconductor materials. As a direct band gap semiconductor, ZnO becomes a very prospective materials for solar energy converting because of its multiple morphology and excellent photoelectrical properties.In this thesis, TiO2/ZnO,HfO2/ZnO, Al2O3/ZnO core-shell structure and3dimensional ZnO nanostructure are prepared based on1dimensional ZnO nanowire arrays modification. The effect of photo-generated charge separating on solar energy converting is discussed.TiO2/ZnO core-shell structure is prepared by facile sol-gol method. Coating of TiO2not only prevents ZnO from the corrosion of acid dye solution, but also improve the separation of the photo-generated electron-hole pairs. The Dye-sensitized solar cells with TiO2/ZnO structure as photo anode reach a photoelectric conversion efficiency of3.0%, when the shell thickness is-10nm.HfO2/ZnO, Al2O3/ZnO core-shell structure are prepared by atomic layer deposition method. After30cycles deposition, an optimized shell thickness is achieved and the degradation efficiency of Rh-B solution with the HfO2/ZnO core-shell reaches six times than that of bare ZnO does at500W Xe lamp irradiation. The charge separation is studied by PL spectrum and the adsorption of dye molecules on material surface is also discussed. However, A12O3modification does not performed as well as HfO2does. The possibly reason has been motioned.3dimensional ZnO nanostructure is prepared by a two-step method. The enhanced specific surface area leads to a high photoactinic activity.