Synthesis And Characterization Of Long-Lasting Nano-phosphors

Long-lasting afterglow materials have potential applications in safety indicators, fluorescent lamps, urgent illumination system, cathode ray tubes, et al. If these compounds were fabricated in the form of one-dimensional nanostructures, they can be widely developed as a new kind of luminescence labels. Aims at controllable preparation technology, characterization technology, and biomarker technology of functional lanthanide fluorescence nanoparticles, based on developments of lanthanide luminescent material. This paper used systematically investigated the controlled synthesis and optical properties of CaTiO3:Pr3+ and Y2O2S:Eu3+,Mg2-,Ti4+ It shows potential application as luminescence labels in immune analysis.Monodisperse nanometer calcium titanate powder was prepared through hydrothermal method. The effects of reaction conditions on the morphology and structure of the product were studied in details. The results indicated that CaTiO3 powders with satisfactory dispersity and a size of several nanometers can be obtained. The optimal conditions were 200℃for reaction temperature,6 h for reaction time,10 mL for PVA(4 g/L) volume and 18 mL for NaOH (5 mol/L) volume with a constant total volume of 43 mL. The mechanism of PVA was also briefly discussed. The CaTiO3 nano-particles show no aggregation even after sintering at high temperature.Nano-precursor was synthesis by co-precipitation or combustion method, and then Y2O2S:Eu3+ was prepared by vulcanization reactions. The result shows that the precursor, which was prepared by both methods, had homogeneous particle diameter and good dispersal. Y2O2S:Eu3+ prepared by precursor, which was made by co-precipitation method, had a poor dispersal and irregular shape. And Y2O2S:Eu3+ prepared by precursor, which was made by combustion method, had a good dispersal and regular shape. The effects of combustion and vulcanizing conditions on the morphology and luminescent properties of the product were studied in details. The mechanism of dispersant was also briefly discussed. The result shows that Y2O2S:Eu3+ obtained by this method is a kind of red phosphors with excellence properties, such as ideal color purity, batter luminescent intensity and excellent chemical stability. Y2O2S:Eu3+,Mg2+,Ti4+ nanoparticles was prepared with a one step combustion method without of reducing atmosphere. The effects of reaction conditions on the morphology and luminescent properties of the product were studied in details. The result shows that Y2O2S:Eu3+,Mg2+,Ti4+obtained by this method is a kind of red phosphors with excellence properties, such as good dispersivity, batter luminescent, which can be well applied to the preparation of Y2O2S:Eu3+,Mg2+,Ti4+. The reaction temperature is several hundreds degrees lower than the traditional high temperature solid state method. This method is a kind of low-temperature synthesis of sulfur oxide nanoparticles which has a extensive application prospect...