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采用预先球磨、再二次热处理的高温固相合成法,制备了一系列白光LED用红色荧光粉CaWO4:Eu3+,L i+,B i3+,利用XRD,SEM和荧光光谱测试对其进行表征。XRD分析表明,所合成的样品为单一的四方晶系CaWO4,Eu3+,L i+,B i3+离子的先后掺杂使基质的部分衍射峰峰位向小角度移动;SEM照片显示,经过预先球磨制备的样品颗粒比较均一,尺寸约为0.5~3μm范围,结晶性好;荧光光谱测试发现这一系列荧光粉不仅可以被紫外光(254 nm)激发,还能被近紫外光(393 nm)和蓝光(465 nm)有效激发,其主发射峰值位于616 nm(Eu3+离子的5D0→7F2跃迁)的红光;另外详细研究了预先球磨的效果、加入H3BO3做助熔剂的质量分数以及Eu3+,L i+,B i3+离子单掺或多掺时的浓度对该体系荧光粉发光特性的影响。
A series of red phosphors CaWO4: Eu3 +, Li +, Bi3 + were prepared by high-temperature solid-state synthesis using pre-ball milling and re-heat treatment. Their structures were characterized by XRD, SEM and fluorescence spectroscopy. XRD analysis showed that the synthesized sample was a single tetragonal CaWO4, Eu3 +, L i +, B i3 + ions doping the matrix part of the diffraction peak to a small angle shift; SEM photo shows that after pre-ball milling The sample particles are relatively uniform, the size is about 0.5 ~ 3μm range, good crystallinity; fluorescence spectroscopy test found that this series of phosphors can not only be excited by ultraviolet (254 nm), but also near ultraviolet (393 nm) and blue 465 nm), and its main emission peak is located at 616 nm (5D0 → 7F2 transition of Eu3 + ions). In addition, the effects of pre-milling, the mass fraction of H3BO3 as flux, and Eu3 +, Li + Effect of i3 + Ion Concentration on the Luminescent Properties of Phosphors in the System.