The Stannate Nanophosphors Preparation And Characterization Of Materials

With the rapid development of nanotechnology, nanomaterials have drawn much attention and been the hot topic because these materials have many miraculous properties compared with the bulk materials. Stannates have excellent thermal and chemical stability. Their luminescence properties, however, has not drawn enough attention. In this paper, we have utilized different synthesis processes to synthesize various stannates and investigated the influence of synthesis process and doped ions on the morphology and luminescence properties for the first time.The main contents are summarized as follows:1. We have synthesized La₂Sn₂O₇ by using a simple coprecipitation method through two reversed processes and investigate the influence of europium ion and dysprosium ion on the luminescence property of the host. When the nanocrystals are synthesized by common-drop method, the final product is obtained directly by the recombination among the ions in -La-O-Sn- colloid structure and the particle size is large. When the nanocrystals are synthesized by reverse-drop method, the final product is obtained by the reaction between hydroxides and the particle size is small to make the luminescence intensity increase. To Eu³⁺-doped La₂Sn₂O₇. There is no concentration quenching though the doping is till up to 12mol%. A concentration quenching occurs in Eu³⁺, Dy³⁺-codoped La₂Sn₂O₇ phosphor host when the Dy³⁺ ion concentration is up to 5mol%. We have synthesized the nanorods of La₂Sn₂O₇ phosphors by using the ethanol solvent and investigated the formation mechanism and the difFerence of the nanocrystals with different morphologies. With the change of the calcination temperature, the final products obtained with three processes from needle-like nanocrystals to nanorods to large nanoparticles. The luminescence properties are different because of the different morphologies. The nanorods with definite morphology can be used as high-quality phosphor.We have synthesized La₂Sn₂O₇ nanocrystals by combustion method using urea as fuel and investigated the influence of Dy³⁺ ion of the luminescence property of the...