Synthesis And Properties Of Rare Earth Compounds Nanomaterials

Rare earth doped luminescent nanomaterials have important applications in high-resolution display, fluorescence label, biological imaging, diagnosis and therapy of diseases and etc. Rare earth phosphors using phosphates as matrix have attracted considerable attention of the researchers. Nowadays, the researches on rare earth phosphates luminescent nanomaterials are focused on the morphology of nanoparticles. The investigation on one-dimensional rare earth phosphates nanomaterials is rarely reported. Therefore, the fabrication of one-dimensional rare earth ions-doped rare earth phosphates will be a meaningful subject. Rare earth coordination compounds-doped polymers are a kind of very valuable functional materials that have both the luminescence properties of rare earth ions and the characteristics of polymer materials. The prepared materials have excellent luminescent properties and high stability. Nanofibers prepared by doping of rare earth coordination compounds in the polymer are a new kind of luminescent materials, and have become a new and important subject of study. Rare earth doped garnet type ferrite is considered as a kink of the most promising media of magneto-optical recording, due to its stability performance of physical and chemistry characters.The main research contents of this thesis are:(1) Eu3+doped phosphates fluorescent nanomaterials with excellent luminescent properties were prepared by hydrothermal method. The influences of synthesis conditions on sizes, crystal structures and morphologies of the phosphates nanomaterials were investigated. The results showed that the luminescent properties of the phosphates nanomaterials were related with the structure and morphology of the as-prepared nanomaterials. And it was practicable to control the luminescent properties of the phosphates nanomaterials by changing the structure of the nanocrystalline.(2) Energy transfer from Ce3+to Tb3+is known and can be found in many luminescent materials. In this dissertation, CePO4:Tb3+nanorods were prepared via hydrothermal method. Sizes, crystal structures and morphologies of the products were investigated by introducing different amounts of CTAB and altering the reaction temperature. Some new meaningful results are obtained.(3) The Eu(TTA)3ECIP/PS composite nanofibers were fabricated by electrospinning. The influences of synthesis conditions on sizes and morpHologies of the composite fibers were investigated. On this basis, we researched the luminescent and oxygen-sensing properties of the composite fibers with different doping concentrations. Experimental data suggested that the Eu(TTA)3ECIP/PS nanofibers exhibited a high sensitivity towards oxygen with a good linear relationship. In addition, the Eu(TTA)3ECIP/PS nanofibers owned a quick response along with its excellent atmospHere insensitivity and pHotobleaching resistance. All these results suggested that the Eu(TTA)3ECIP/PS system were promising candidates for oxygen sensing optical sensors. At the same, we explored the method to prepare the aligned fibers with double collectors. The formation mechanism of the aligned fibers between the collectors was also discussed.(4)(TbY)3Fe5O12with garnet structure were produced via sol-gel method. The structure and formation mechanism were studied. Also, we investigated the influence of rare earth doping on the magnetic properties of the nanoparticles.