• Title/Summary/Keyword: multi-sten precipitation

Search Result 1, Processing Time 0.014 seconds

Preparation and Properties of Spherical BaMgAl10O17:Eu Phosphor by Multi-step Precipitation Method (다단 침전법에 의한 구형 BaMgAl10O17:Eu 형광체의 제조 및 특성)

  • Park, Jumg-Min;Jung, Ha-Kyun;Park, Hee-Dong;Park, Yoon-Chang
    • Korean Journal of Materials Research
    • /
    • v.12 no.11
    • /
    • pp.840-844
    • /
    • 2002
  • A spherical $BaMgAl_{10}$ $O_{17}$ :Eu phosphor has been synthesized by a multi-step precipitation route. In order to successfully synthesize the phosphor with spherical shape, the hydrated-alumina particles should be controlled for spherical shape. In this process, the hydroxypropyl cellulose (HPC) was used as a dispersing reagent. This reagent plays an important role in that the particles were controlled to have the uniform size of sub-micron. The final product prepared by the multi-step precipitation method maintained spherical shape with uniform size of 0.4$\mu\textrm{m}$. It can be seen in X-ray diffraction patterns, formation of the single phase of $BaMgAl_{10}$ $O_{17}$ :Eu phosphor prepared by the multi-step precipitation method at $1350^{\circ}C$. Also, the emission spectra of spherical $BaMgAl_{O}$ $10_{17}$ :Eu phosphor in the present case was compared with those of commercially-available blue phosphor under VUV (Vacuum Ultra Violet) excitation. The luminescence process of the $BaMgAl_{10}$ $O_{17}$ :Eu phosphor is characterized by the $4f^{6}$$5d^1$longrightarrow4f$^{7}$ transition (blue) of the $Eu^{2+}$ ion acting as an activating center and the maximum luminescence intensity was obtained by reduction treatment at 145$0^{\circ}C$.