摘要我们经高温固相法合成了两个系列的单一基质荧光粉:Ca9MgNa(PO4)7:Eu2+荧光粉和Ca9MgNa(PO4)7:Eu2+,Mn2+荧光粉。调节晶体场分裂和能量转移,我们可以将它的颜色从蓝经绿最后调到红色。通过测试Mn2+浓度对发光性能的影响,我们发现共掺不同浓度的Mn2+能引起Eu2+的发光发生变化。此外Mn2+离子的激发光谱和Eu2+离子的发射光谱重叠导致从Eu2+离子到Mn2+离子间的能量转换。发光寿命延迟经电偶极-电四极相互作用机理产生了共振型能量转化。结果表明Ca9MgNa(PO4)7:0.005Eu2+,0.01Mn2+和Ca9MgNa(PO4)7:0.005Eu2+,0.03Mn2+的荧光粉均有较为良好的发光性能,对近紫外白光LEDs有潜在的使用价值。19710
毕业论文关键词:高温固相合成;Eu2+;Mn2+;荧光粉;白光;
Abstract
Two series of single-composition Ca9MgNa(PO4)7:Eu2+ and Ca9MgNa(PO4)7:Eu2+,Mn2+ phosphors were synthesized via high-temperature solid-state reactions. Their emission colors could be tuned from blue to green and eventually to red through tuning the crystal field splitting and energy transfer. On examining the Mn2+ concentration-dependent photoluminescence properties, we found that co-doping with Mn2+ would lead to a change in Eu2+ ratio. Moreover, an energy transfer fromEu2+ to Mn2+ occurs because of the spectral overlap between the emission band of Eu2+ and the excitation band of Mn2+. The resonance-type energy transfer via a dipole–quadrupole interaction mechanism was supported by decay lifetime data . .The results suggest that Ca9MgNa(PO4)7:0.005Eu2+,0.01Mn2+ and Ca9MgNa(PO4)7:0.005Eu2+,0.03Mn2+ phosphors have a super and are Superior performance potentially useful for white n-UV light-emitting diodes (LEDs).
Keywords: High-temperature solid-state reactions;Eu2+;Mn2+;Phosphors;white-light;
目 录
1.绪论 4
1.1引言 4
1.2白光发光二极管 4
1.2.1白色LED的实现途径 6
1.2.2白光LED的性能指标 7
1.3发光材料 9
1.3.1不同基质的研究 11
1.3.2稀土离子间的能量传递 12
1.3.3 Eu2+离子的发光特性 13
1.4荧光粉的主要合成方法和优缺点 13
1.5本论文的研究内容和目的 14
1.5.1论文研究内容 14
1.5.2论文的研究目的 15
2. 实验部分 15
2.1实验仪器与试剂 16
2.1.1实验仪器 16
2. 2.2实验试剂 16
2.2样品的制备和测试手段 16
2.2.1实验配比的计算 16
2.2.2实验过程 17
2.3性能表征 17
2.3.1晶相结构分析 17
2.3.2荧光光谱测试 17
2.3.3光色参数测试 17
2.3.4荧光寿命测试 17
2.3.5紫外吸收测试 18
2.3.6 SEM测试 18
3.实验结果与讨论 19
3.1 Ca(1-x)9MgNa(PO4)7:xEu2+性能研究 19
3.1.1样品的晶相结构分析 19
3.1.2样品SEM分析 19
3.1.3样品的紫外吸收 20
3.1.4 样品的激发、发射光谱 21
3.1.5样品的光色参数分析 21
3.2 Ca(1-0.005-y)9MgNa(PO4)7:0.005Eu2+,yMn2+性能研究 22
3.2.1样品的晶相结构分析 23
3.2.2样品SEM分析 23
3.2.3紫外吸收 24
3.2.4发射光谱 25
3.2.5光色参数分析 26
3.3荧光寿命研究 27 Ca9MgNa(PO4)7:Eu2+,Mn2+白光发射荧光粉的制备与发光性能的研究:http://www.youerw.com/cailiao/lunwen_11172.html