Improvement Of The Photoluminescent Properties Of BaMgAl₁₀O₁₇:Eu²⁺, Mn²⁺and （Ce,Tb）MgAl₁₁O₁₉Phosphors Of Compact Fluorescent Lamp

Tricolor compact fluorescent lamp is widely used at the call of "Green Lighting" because of the characteristics such as long service life, excellent color index, color temperature adjustable, energy saving, no radiation pollution, and so on. Tricolor phosphors for compact fluorescent lamp exhibit excellent photoluminescence excited by ultraviolet. At present, the commercial tricolor phosphors are red Y2O3:Eu2+, blue BaMgAl10O17:Eu2+/BaMgAl10O17:Eu2+, Mn2+(BAM) and green (Ce,Tb)MgAl11O19(CMAT). However, the problems of ricolor phosphors become obvious with the tricolor compact fluorescent lamp widely used. The thermal and the ultraviolet radiation degradation appears in lamp-making and daily use due to BAM phosphor’s structure limitation, effecting the color and service life of compact fluorescent lamp seriously. The CMAT phosphor powders were prepared by conventional high-temperature solid state reaction in industrial production. But the phosphors sintering to agglomeration seriously and must to be through ball milling in order to get uniform size phosphor although the simple synthesis process and equipment. Milling process reduces the brightness of phosphors due to the damages of surface structure. In this paper, some experimental work was done for improving the photo luminescent properties of BaMgAl10O17:Eu2+,Mn2+and (Ce,Tb)MgAl11O19phosphors. The main works were contained as below:1. The thermal and the ultraviolet radiation degradation mechanisms of BaMgAl10O17:Eu2+, Mn2+phosphor are investigated in a comparative way. The difference between the thermal and the ultraviolet radiation degradation mechanisms have been found through emission spectra, absorption spectra, thermoluminescence spectra and ICP analysis data.2. The effect of flux on (Ce,Tb)MgAl11O19phosphor through high-temperature solid state reaction is studied. The photoluminescence of (Ce,Tb)MgAl11O19phosphor was improved due to the addition of complex flux.Thermal and ultraviolet radiation treatments can both seriously damage the luminous efficiency of BaMgAl10O17:Eu2+,Mn2+. It is revealed that the thermal degradation is involved in the oxidation and migration of Eu2+ions. The ultraviolet radiation makes the Eu2+in metastable state, which weakens the direct absorption of Eu2+and thus reduces the relative luminescence intensity of BaMgAl10O17:Eu2+,Mn2+. The H3BO3+AIF3+NH4F flux ratio was optimized to prepare the (Ce,Tb)MgAl11O19phosphor powders with fine dispersion, regular morphology, high brightness.