| Rare earth doped alkaline earth aluminate and silicate has obtained widely application. At present, the best green or blue long decay phosphor is SrAl2O4:Eu2+,Dy3+ and SrAl2O4:Eu2+,Nd3+. Their chemical properties, emission intensity and decay time are similar. According to tricolor principle, any color long decay phosphor can be obtained when we mix red, green and blue long decay phosphors at a proper proportion, if their chemical properties, emission intensity and decay time are similar. Or else, the color of the mix phosphor will change during the decay process. But now, there is not a kind of red long decay phosphor can match theses two.MTiO3:Pr(M=Mg,Ca,Sr,Ba) is a new kind of red long decay phosphor. MTiO3:Pr exhibits red cathodoluminescence located at x=0.68 and y=0.31 in the CIE coordinate. Furthermore, the CIE coordinate is very close to that of the NTSC "ideal red" which makes CaTiO3:Pr has great potential application value.The red long decay phosphor , with the nominal formula Ca0.8Zn0.2TiO3: Pr, is a mixed phase which contains three crystal phases CaTiO3, Zn2TiO4 and Ca2Zn4Ti15O36. But the emission intensity of Ca0.8Zn0.2TiO3:Pr is much more stronger than CaTiO3:Pr. However, Zn2TiO4:Pr has no emission. Therefore, on this paper, we studied the synthesis and luminescent properties of Ca2Zn4Ti15O36:Pr; studied the luminescence improvement; studied the luminescence mechanism of Ca0.8Zn0.2TiO3:Pr.1. Synthesis Ca2Zn4Tii5O36:Pr by solid state reaction.Mixing CaC03,Zn0 and TiO2 with a molar ratio of 1:2:7.5, adding proper amount of Pr3+ and Na+ ion, drying, sintering the mixed materials at 1200°C in air atmosphere for 48- 96 hours, then obtain the samples.The analysis results indicates that pure Ca2Zn4Ti15036 can be obtained when it is sintered at 1200 °C for 48h. The product Ca2Zn4Ti15O36:Pr is a new kind of red long decay phosphor. Its main excitation peak located at about 330nm while its emission peak located at about 618nm.Ca2Zn4Ti15036:Pr is a chemical stable phosphor and decays much slower than CaTiO3:Pr and Cao.8Zn0.2Ti03:Pr. But weak emission intensity is its fatal shortcoming.2. Synthesis Ca2Zn4Ti15O36:Pr by sol-gel method.The materials are n-titanium butoxide, citric acid, ethylene glycol, Ca(NO3)2.4H2O, Zn(NO3)2.6H2O and Pr(NO3)3. Polymer precursor was obtained after a series of physical and chemical processes. Most Ca2Zn4Tii5O36:Pr can be obtained by sintering the polymer precursor at 700°C for 12h; however, pure aim products can be obtained by sintering . the polymer precursor at 1000°C for 24h. The photoluminescence spectra shape of the product synthesized by sol-gel method was not changed. However, the emission intensity at 618nm improved 510% and the particle size is much smaller and much uniformer than the product synthesized by solid state reaction.3. Synthesis Ca2.,vMxZn4Tii5036:Pr(M=Mg,Sr,Ba) by solid state reaction.We changed the properties of Ca2Zn4Tii5036: Pr by changing the matrix through alkaline metal doped to form new phosphors with the formula of Ca2.xMxZn4Ti15O36:Pr(x=0,0.5,1.0,1.5,2). With the...
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