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采用共沉淀法制备了Ca_(0.93-x)(Mo_(0.9)W_(0.1))O_4∶Eu_(0.07)~(3+),Bi_x~(3+)(0≤x≤0.05)系列样品,通过XRD、SEM及荧光光谱仪对粉体的晶体结构、形貌及荧光性能进行测试和表征。结果表明,Bi~(3+)、Eu~(3+)及WO_4~(2-)的掺杂没有改变CaMoO_4原有的四方晶系体心结构,且样品粒径分布较均匀,无明显团聚现象。随着Bi~(3+)的掺杂,Ca_(0.93-x)(Mo_(0.9)W_(0.1))O_4∶Eu_(0.07)~(3+),Bi_x~(3+)样品的激发光谱带边会发生红移,且激发强度呈现先增强后减弱的趋势,其发射光谱也具有相应的规律,Bi~(3+)的最佳掺杂浓度为x=0.02 mol,在395 nm激发下,样品的发光强度提升至134%;较之商用红色荧光粉Y_2O_2S∶Eu~(3+),Ca_(0.91)(Mo_(0.9)W_(0.1))O_4∶Eu_(0.07)~(3+),Bi_(0.02)~(3+)样品显现出更好的色纯度和发光强度,适合于近紫外LED用红色荧光粉。
The samples of Ca_ (0.93-x) (Mo_ (0.9) W_ (0.1)) O_4:Eu_ (0.07) ~ (3 +) and Bi_x ~ (3 +) (0≤x≤0.05) were prepared by coprecipitation method. The crystal structure, morphology and fluorescent properties of the powders were tested and characterized by XRD, SEM and fluorescence spectroscopy. The results show that the doping of Bi 3+, Eu 3+ and WO 4 2- does not change the original tetragonal core structure of CaMoO 4, and the particle size distribution is more uniform with no obvious agglomeration phenomenon. The excitation spectra of Ca_ (0.93-x) (Mo_ (0.9) W_ (0.1)) O_4:Eu_ (0.07) ~ (3 +) and Bi_x ~ (3 +) samples with the doping of Bi ~ The band edge will redshift, and the excitation intensity first increases and then weakens. The emission spectrum also has a corresponding rule. The optimal doping concentration of Bi 3+ is x = 0.02 mol. Under the excitation of 395 nm , The luminescence intensity of the sample increased to 134%. Compared with commercial red phosphor Y_2O_2S:Eu ~ (3 +), Ca_ (0.91) (Mo_ (0.9) W_ (0.1)) O_4:Eu_ (0.07) , The Bi_ (0.02) ~ (3+) samples showed better color purity and luminescence intensity, which is suitable for the red phosphor for near ultraviolet LED.