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SrAl_(12)O_(19):Mn~(4+)是一种用于高显色性白光发光二极管的候选红色荧光材料。本论文研究了Mg~(2+)、Zn~(2+)和Ge~(4+)离子的掺杂效应以及Ga~(3+)、Ca~(2+)和Ba~(2+)离子的取代效应对SrAl_(12)O_(19):Mn~(4+)荧光材料性能的影响。样品通过高温固相反应制备,焙烧温度在1250~1500℃之间。利用X射线衍射技术表征了材料的相纯度,用荧光激发光谱和发射光谱表征了材料的荧光性能。研究结果指出,与未进行Mg~(2+)或Zn~(2+)掺杂的样品相比,Mg~(2+)或Zn~(2+)离子对Al~(3+)格位的掺杂可以使材料的发光强度提高~60%,其原因被认为是掺杂促进了激活剂Mn~(4+)离子进入晶格,其过程可以表示为:MO+MnOM_(Al)’+Mn_(Al)+30o~×(M=Mg,Zn),电子顺磁共振谱支持这一结果。Ge~(4+)离子的掺杂使材料的发光性能明显下降。Ga~(3+)离子可以取代Al~(3+)离子形成全范围的固溶体,其中少量Ga~(3+)离子的掺杂可以使材料的荧光发射强度提高~13%,而掺杂量进一步提高使材料的荧光性能下降。Ca~(2+)和Ba~(2+)对Sr~(2+)的取代仅形成有限范围的固溶体。Ca~(2+)的取代使材料的发光性能提高;而Ba~(2+)的取代使材料的发光强度下降。
SrAl_ (12) O_ (19): Mn ~ (4+) is a candidate red fluorescent material for high color rendering white light emitting diodes. In this thesis, the doping effects of Mg 2+, Zn 2+ and Ge 4+ ions as well as the effects of Ga 3+, Ca 2+ and Ba 2+ Effect of Substitution Effect on Properties of SrAl_ (12) O_ (19): Mn ~ (4+) Fluorescent Material. Samples prepared by high temperature solid-state reaction, calcination temperature between 1250 ~ 1500 ℃. The phase purity of the material was characterized by X-ray diffraction. The fluorescence properties of the material were characterized by fluorescence excitation and emission spectroscopy. The results show that compared with the samples without Mg 2+ or Zn 2+ doping, the effect of Mg 2+ or Zn 2+ ions on the lattice of Al 3+ Doping can increase the luminescence intensity of the material by ~ 60%. The reason for this is believed to be that the doping promotes the entry of Mn ~ (4 +) ions into the crystal lattice. The process can be expressed as: MO + MnOM_ (Al) ’+ Mn_ (Al) + 30o ~ × (M = Mg, Zn). Electron paramagnetic resonance spectra support this result. The doping of Ge ~ (4 +) ions significantly decreased the luminescent properties of the materials. Ga ~ (3+) ions can replace Al ~ (3+) ions to form a full range of solid solution, in which a small amount of Ga ~ (3+) doping can increase the fluorescence emission intensity of the material by ~ 13% Further improve the fluorescence properties of the material decreased. The substitution of Ca 2+ and Ba 2+ for Sr 2+ forms only a limited range of solid solutions. The substitution of Ca 2+ enhances the luminescent properties of the material, while the substitution of Ba 2+ reduces the luminescence intensity of the material.