The Thermal Stability Study Of Synthesized BaMgAl₁₀O₁₇:Eu²⁺, Mn²⁺ For Compact Fluorescent Lamp

Eu2+activated BaMgAl10O17:Eu2+(BAM), as a blue phosphor, was widely used in commercial applications such as plasma display panels (PDP), high definition television (HDTV), field emission displays (FEDs) and fluorescent lamps (FL) because of its high luminance efficiency and good color purity. The traditional high temperature solid phase reaction was used to prepare BAM in industry and the resultant temperature was higher than1550℃. Although this process is stable and the equipment is simple, the heterogeneous of particle size, particle aggregation, irregular morphology and needing to the ball mill processing always exist, which will impair the photoluminescence (PL) property of BAM. On the other side, baking processor belt of the lamps) in air while coating the phosphor surface cause the luminescent efficiency decline and color coordinate offsetting of BAM phosphors, which will affect the display device or fluorescent color rendering index and service life. In order to improve the thermal stability of BAM, our BAM blue phosphor was synthesized by using high temperature solid phase method, and we studied the influence of flux and doped Ca, Zn elements on the structure and photoluminescence properties of BAM. Moreover, Ca, Zn-doped BAM were annealed under air atmosphere at500-600℃and the main results as following:1. The blue phosphors BAM were synthesized in traditional solid-state reaction method by using H3BO3, AlF3, BaF2, LiF and MgF2as a single or multiple fluxes. The influence of different flux concentration on BAM phase, morphology and PL properties has been studied. The results show that after adding flux, synthesis temperature can be reduced100to150℃. In addition, the good dispersity and homogenized particle size of hexagonal BAM was obtained and the results showed that fluoride flux affected the BAM distinctly. When comparing with homemade commercial phosphors, our samples have a higher PL intensity.2. In our study, by decreasing the content of original BaCO3and supplementing Ba2+with flux BaF2that performs as actors of both flux and Ba2+source. Simultaneously, we used fluoride as doped raw material and doped Ca2+into matrix BAM by using CaF2as flux formation. The impurity phase can be limited if the CaF2acts as both dopant and flux. With this technology, we successfully prepared pure phase of BAM. By simulating with belt of the lamp technology, results show that the thermal stability of BAM prepared by this method is higher than domestic commercial powder with an increase of7%to18%.3. Based on above work, we also prepared the BAM:Ca2+, Zn2+samples. The results show that the lattice parameter of doped BAM has decreased, and the PL performance and thermal stability have been improved significantly than that of commercial powder. The relative brightness increased by1%to3%and the thermal stability has a growth of3%to10%higher than that of the domestic commercial phosphors without processing, respectively. Moreover, the color coordinates are more stable.