Preparation And Structural Characteristic Studies Of Nano-Metal Oxside (Sulfide)

The thesis firstly described the basic concept and meaning of nanomaterials andnanotechnology, investigated the properties and preparation methods of nanomaterials.Additionally, the progress of nanomaterials and nanotechnology in our country inrecent years were also discussed. In this thesis, TiO2 nanopowders,bismuth sulfide(Bi2S3) nano-material andcadmium sulfide(CdS) nano-material were selected to find their simple and noveltysynthesis methods. Thus we may provide executable methods for industry productionof these materials. There have been many methods to prepare TiO2 nanopowders. However, thesemethods have many disadvantages respectively. In order to provide a low-cost methodto industrialized product TiO2 nanopowders, we selected a surfactant-controlledhydrolysis method to prepare TiO2 nanopowders. The experiment results showed thatthe surfactant plays a crucial role in the preparation of TiO2 nanopowders. Theinfluences of the kind and amount of surfactant and pH on the preparation of TiO2nanopowders were also discussed. Hydrothermal and solvothermal synthesis are effective methods to preparenanomaterials under milder conditions. Bi2S3 nanopowders and nanorods wereprepared with hydrothermal and solvothermal method at different reaction time andtemperature respectively. The reaction mechanism of Bi2S3 nanopowders andformation mechanism of Bi2S3 nanorods, the effects of temperature and time werediscussed. Bundles of Bi2S3 nanorods were prepared by using surfactant-assistedsolvothermal method. The results showed that surfactant played an important role incontrolling the morphology of the product. The influence of the kind of surfactant onthe bundles of Bi2S3 nanorods was discussed. The possible formation mechanism ofthe bundles of Bi2S3 nanorods was also investigated. The preparation and characterization of II-VI nanoscale compoundsemiconductors have caused much attention in the past several years due to their greatpotential in many optoelectronic application. So far, a number of reactions have beenutilized to prepare II-VI family compounds for quite some time, but there are somelimitations to their utility. Now, there have been considerable efforts to simplify thesynthetic route to II-VI semiconductors and avoid the use of complex reactions and II摘 要toxic reagents. Hydrothermal synthesis is an effective method to prepare metaloxide(sulfide). CdS nanopowders and nanorods were prepared with hydrothermalmethod at different reaction time and temperature respectively.