The Morphology Control Of Rare Earth Oxide Nano Powder And Polymer Surface Modification

Rare earth oxide materials have attracted much attention, for their unique electrical, magnetic, thermal and catalytic properties, etc. It will promote their properties further when they exist in the form as nanomaterials and nanostructures with nano effects. Therefore, nowadays, more and more efforts have been focused on the fabrication of rare earth oxide nanomaterials and construction of their nanostructure.In this paper, focusing on the synthesis and morphology control of the rare earth oxide nanomaterials, several kinds of rare earth oxide nanopowders have been prepared via a novel alcohol-water mixed solvothennal route. The influence of the concentrations of the surfactant, the reaction temperature, the alcohol-water ratio on the particle sizes and size distributions of the powders have been investigated. Also, yttrium oxide, europium oxide nanotubes of fine dispersion have been prepared through a hydrothermal route plus light irradiation for rapid crystallization. Moreover, yttrium or the samarium doped cerium oxide nanopowders have been prepared and the effects of the element type and contents of doping elements on the morphologies of nanoparticles have been clarified. Based on these, yttrium doped cerium oxide/polymer composite microspheres have been successful constructed.Cerium nitrate as raw materials, PVP as stable agent, cerium oxide nanopowders were fabricated via alcohol-water mixed solvothermal route. The results of XRD, TEM and DLS show that:the as-obtained product was of fluorite structure with higher phase purity, grain narrow size distribution and their particle size about60nm. By adjusting the alcohol-water ratio, not only can control the reaction temperature, reaction time, but also can control the product particle size and morphology. At the initial stage of reaction system is homogeneous liquid phase, and other rare earth nitrates could be doped to cerium oxide easily, the particle size was about80nm, the fluorite structure of monodispersed yttrium, samarium doped cerium oxide nanopowders have been successfully fabricated.Rare earth nitrate as raw materials and PVP as a stable agent, the precursor of rare earth oxide nanopowders were synthesized via alcohol-water mixed solvothermal route. The spherical nanopowders of europium oxide, yttrium oxide, and with hollow structure of the lanthanum oxide can been prepared after the precursor calcined at the high temperatures. This synthetic route could be also widely applied to the synthesis of other rare earth oxide nanomaterials.The results of XRD and TEM show that:the yttrium hydroxide and the europium hydroxide nanotubes have been fabricated by the hydrothermal route, and then the as-obtained products could changed to yttrium oxide, europium oxide nanotubes with good dispersion by the light irradiation for5min.Based on the electrostatic interaction between the positive charge on the surface of the as-prepared yttrium doped cerium oxide nanopowders and the negative charge on the poly (styrene-acrylic acid) microspheres from free emulsion polymerization, the rare earth oxide/polymer composite microspheres have been synthesized. The composite microspheres have a certain amount of carboxyl on the surface, which can be carried out the grafting reaction with amino silicone oil. And the product could be used into good stability against sedimentation ER materials. The surface of yttrium doped cerium oxide nanopowders has been modified by the zwitterionic surfactant3-(N, N-Dimethylmyristylammonio) propanesulfonate. Besides that, yttrium doped cerium oxide/PMMA composite nanoparticles were successfully fabricated via solution polymerization and the composite nanoparticles were characterized with a clear core/shell structure and the shell thickness of PMMA about10nm.