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Plasma display panel (Plasma Display Panel PDP) to become the research focus of the current large-screen display technology has a large screen, wide viewing angle, high definition, light weight, fast response, and many other advantages. BaMgAl 10 O 17 : Eu 2 (BAM) blue phosphor because it has a high quantum efficiency and color purity, as well as in the vacuum ultraviolet with excellent luminous efficiency and is widely used in the PDP. For a long time the industrial synthesis of BAM blue phosphor using the traditional high-temperature solid-phase method. Although the law process is simple, easy to implement large-scale production, but the synthesis process generally 1600 ° C insulation for a long time, the production process is also often due to raw material mixed uneven, causing the reaction is not complete and contains alpha-alumina (alpha-al 2 O 3 ), barium aluminate (Baal 2 O 4 ), magnesium aluminate (MgAl 2 O 4 ) and other miscellaneous these Miscellaneous absorb ultraviolet radiation and visible light due to the light fades. Meanwhile, solid-phase synthesis of BAM phosphor particles were hexagonal platelets, the particle size distribution is broader. This powder materials, poor mobility, is not conducive to a painted screen, the need for further milling, ball milling will destroy the BAM crystal structure of the light-emitting phosphor performance degradation. Therefore, the study of new technology to prepare a \In this paper, aluminum ammonium sulfate, barium nitrate, magnesium nitrate, europium nitrate and sodium carbonate as raw materials, control reaction precipitation Preparation of Spherical BaMgAl was 10 the O 17 : Eu 2 blue phosphor process and BAM crystal structure and luminescence properties of the phosphor powder. Using a scanning electron microscope (SEM), X-ray diffraction (XRD) characterization of the spherical precursor and its calcined product morphology, structure and composition; thermogravimetry - differential scanning calorimetry (TG-DSC) analysis of the precursor The thermal decomposition process of the body; using laser particle size analyzer and the particle size distribution of the powder particles; PMS-3 fluorescence analysis system on the the prepared BAM blue phosphor luminescence properties were tested by fluorescence spectrophotometer. The study found that the temperature, the molar ratio of metal ion, the pH value of the solution, the average residence time of the particles in the reactor, the amount of incorporation of rare earth ions and the heat treatment temperature and time are the main factors affect the structure of the product and performance. Experimental results show that at a temperature of 25 to 30 ° C, the metal ions mole ratio of Ba 2 : the Mg 2 : the Al 3 : Eu 3 = 0.88:1.2:10:0.12, pH about 7.8, the particles in the reactor, the average residence time of 6h total reaction time is continuous through-feed is controlled at about 30h, stirring speed 1000rpm conditions under Built spherical precursor BaSO 4 , Al (OH) 3 , MgCO 3 and Eu (OH) 3 a mixture of the precursor at 1300 ℃ activated carbon thermal reduction for 3h spherical BaMgAl 10 the O 17 : Eu for 2 blue phosphor. Spherical BAM blue phosphor was prepared under the process conditions of this optimization is relative emission luminance of 104%, and the chromaticity coordinates x = 0.1446, y = 0.0620, correlated color temperature of 25000K, D50 = 7.20μm, an average particle size of 7.50μm, the particle size distribution between 5 to 8μm emission spectrum peak at 449 nm, and thermal stability than the solid-phase synthesis of blue powder there was a marked improvement.
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