Syntheses And Electrochemistry Of Nanostructured Rare Earth Functional Materials

Nanomaterials are also called nano-scale structure materials, broadly speaking itis the materials that at least have one-dimensional in nanometer size. October18,2011the European Commission defined the nanomaterials as natural or artificialmaterial which are composed of basic particles. The nanomaterials general have twobasic characteristics, one is that the size of the material is between1to100nanometers, the other is that nanomaterials have special physical and chemicalproperties compared to conventional materials. As a new novel material in thiscentury the nanomaterials have great research value and practical applications. Therare earth atoms have special electronic shell structure, the outer electrons is almostthe same, but the inner layer have many unfilled4f orbitals, which make them easyto react with other substances. Rare earth elements have been widely used inelectronics, petrochemical, metallurgy, machinery, energy, military, light industry,environmental protection, agriculture and other fields in recent years. The rare earthmaterial in nanoscale structure can have characteristics of both nano-materials andearth materials, so the application performation is enhanced greatly, therefore toscientists the nano rare earth materials have become a hot research topic. The mainresearch content and work can be summarized as follows.1. In the first and second part, we prepared some rodlike rare earth nanoparticls,such as NaCe（MoO₄）₂、KCeMo₂O₈、Na_xK_1-xCeMo₂O₈，and platelike nanoparticlssuch as NaY（MoO₄）₂via the hydrothermal treatment. We found that the condition ofthe chemical reaction, such as reaction time、reaction temperature and reactionsolvent have great influence to the morphologies of NaCe（MoO₄）₂、KCeMo₂O₈andNa_xK_1-xCeMo₂O₈. The electrochemical performance of the samples was tested bycyclic voltammetry and showed good character. On this basis, try to study thedifferent of type and morphology after adding fluoride to the resultant.2. By using sodium fluoride, sodium molybdate and yttrium nitrate as rawmaterials, three rare earth fluorides are synthesized by using different solvent, whenusing ethylene glycol as solvent the product is α-NaYF₄, which morphologie is spherical with rough surface, when it comes to water, the product is YF₃nanomaterials with platelike and rob-like morphology, when it comes to water andethylene glycol as mixed solvent, the product is β-NaYF₄rob-like morphologynanomaterials.3. In the basis of the original synthetic materials, we designed mutual conversionexperiments by using three substances α-NaYF₄, YF₃and β-NaYF₄, the products’structures and morphologies are characterized by SEM and XRD after conversion.The electrochemical performance of these samples was tested by cyclic voltammetryand showed good character. The meaning and purpose of this experimental is toobtain any one of these three substances by changing the reaction conditions.