Solid-state Synthesis And Characterization Of Low-dimension CdS,ZnS And ZnO Nanomaterials

Nanostructured metal oxides and sulfides have exhibited unique physical chemical properties. Preparing and investigating their general formation mechanism may be a solution to the precise control of their sizes and properties. Conventional synthesis is always performed in solution or gas, and it is being excluded due to many problems more and more.In this dissertation, according to command of energy-economical and green effective production, different sulfides and oxides have been synthesized and characterized by low-temperature solid-state, molten salt and microwave solid-state in the presence of addition, respectively. Their formation mechanism has been explored, and their optical and electrical properties have been also characterized.CdS nanomaterials had been synthesized by low-temperature solid-state reaction in the condition of different reaction temperature, different time and different additions, and UV-vis properties depend on diameter and crystal pattern of products. Crystal pattern and diameter of CdS nanoparticles can be controlled by different additions and reaction temperature, and their formation mechanic has been explored; Diameter of CdS nanoparticles can also control by adding template terephthalic acid in the reaction; Hexagonal CdS nanoparticles are synthesized by using choline chloride as molten salt under low reaction temperature; CdS nanoparticles had also been synthesized by microwave-assisted solid-state reaction, and radiation time and radiation pattern have some effect on diameter and crystal pattern of products; On the contrast, CdS nanoparticles synthesized by low-temperature solid-state reaction got best qulity.Diameter of ZnS nanoparticles is affected by reaction temperature, reaction time and additions, and ZnS nanoparticles with small diameter can be obtained by using dodecylamine as addition; ZnS hexagonal prism can be synthesized simply by using NaCl as molten salt, and the effects of reactants, molten-salts and additions on product morphologies have been studied; On the contrast, different methods can be chosed to obtain ZnS with different morphologies and different properties.In the condition of changing molten salts and reactants, ZnO with different morphologies can be obtained, and product morphologies depend on molten-salt and reactants; The effect of molten-satle on ZnO nanoparticles had studied, and results show that additional molten-satle provided a favorable environment for growth of ZnO particles; In the presence of PEG400, ZnO nanorods had been synthesized, and studies show that microwave radiation can lead to fast synthesis of ZnO nanorods and PEG400 can confine the growth rate in some directions. Thus, ZnO products with different morphologies and different properties had been obtained.Co₃O₄ nanorods had been obtained by employing Co nanoparticles as precursor and using NaCl-KCl molten salt, results show that Cl- leads to formation of Co₃O₄ nanorods, and different precursors and different molten-salts have great effects on products morphologies; Co₃O₄ nanoparticles with a fine electrochemical stability had been synthesized in the presence of addition and molten-salt. Different methods can be chosed to obtain Co₃O₄ with different morphologies.Metal Ni and electrode materials NiO have been synthesize through microwave-assisted and addition-assisted reactions, and studies show that reaction temperature, reaction time and mixed state between precursor and addition all had important effects on formation and sizes of the products.In addition, metal Ag and metal coordinate compound PbC₂O₄ had been synthesized by low-temperature solid-state reaction. Metal Cu has been also obtained by microwave radiation in the presence of PEG400, and radiation time has an important effect on formation of Cu nanoparticles.The studies about metal oxides and sulfides are a new development of solid-state reaction, and it can provide useful reference for synthesis of nanomaterials with different morphologies and different properties, and large-scale produce and application of nanomaterials, and it may have an important research value and wide application future.