白光LED用纳米玻璃的合成和光谱特性(含任务书,开题报告,外文翻译,毕业论文9100字,答辩PPT)
摘要
MgGa2O4既是一种有重要应用价值的新型蓝色荧光体，又是一种适合稀土掺杂的发光基质。本文通过溶胶-凝胶法对其掺杂稀土离子(Eu3+，Dy3+)从而合成新型的复合发光材料，并研究在不同的MgO-Ga2O3配比和不同的温度（700 oC，800 oC，900 oC）下此材料的晶化能力和发光强度，分析对比从而获得最佳方法。通过对样品进行XRD分析和荧光光谱分析，发现随着MgO-Ga2O3量的增加和温度的升高，样品晶化能力变强，形成的MgGa2O4纳米晶将稀土离子稀释，从而经历了浓度猝灭、解猝灭和稀释的过程，发光强度相应经历弱-强-弱的变化。通过对比分析，在MgO-Ga2O3-SiO2中掺杂稀土离子Eu3+的最佳配比为2MgO-2Ga2O3-96SiO2:Eu3+，其在395 nm激发下发出强烈的单色红光。而掺杂稀土离子Dy3+的最佳配比为5MgO-5Ga2O3-90SiO2:Dy3+，其在在350 nm激发下能发出强烈的蓝光(487 nm)和黄光(578 nm)，通过调节可实现白光发射。而且这两种配比在350 nm激发下都比240nm的强。这表明，氧化物玻璃中掺杂稀土离子发光材料的研究在白光LED领域具有十分重要的作用和意义。
关键词：玻璃陶瓷；稀土掺杂；溶胶凝胶；晶化能力；发光强度；最佳配比
White LED synthesis with nano glass and the spectral characteristics
Abstract
MgGa2O4 is not only a new blue fluorescent with great value, but also a suitable rare earth doped luminous matrix. In this paper, the rare earth ions (Dy3+,Eu3+)-doped MgO-Ga2O3-SiO2 glass-ceramic was prepared by sol–gel method to Synthesis new type of composite light-emitting materials, and studied in at different MgO- Ga2O3 ratio and different temperatures (700 oC，800 oC，900 oC) the crystallization ability and the luminous intensity of this material , analysis and comparison to get the best methods. The samples were analyzed by means of XRD and fluorescence spectroscopy, found that with the increasing in the amount of MgO-Ga2O3 and the heat treatment temperature, the crystalline ability of samples was increased. As MgGa2O4 nanocrystalline increase, resulting in the rare earth ions was relatively diluted. The rare earth ions experienced a concentration quenching, the solution of quenching and dilution process, and the luminous intensity corresponding to experience weak-strong-weak change. Through comparative analysis, the best compositions of samples doped with Eu3+ were: 2MgO-2Ga2O3-96SiO2:Eu3+, it can emit a very strong pure red(626nm) light under the excitation of 395nm ;and 5MgO-5Ga2O3-90SiO2:Dy3+,which can emit stronger blue (487 nm) and yellow ( 578 nm ) light, and white light emission can be achieved by adjusting the composition.and both these two samples emit at 350 nm stronger then 280nm. which shows the MgO–Ga2O3–SiO2 doped with rare earth ions have the potentiality to be used into the field of white light LEDs applications.
Keywords: Glass-ceramic; Rare earth doped; Sol-gel; Crystallization ability; Luminous intensity; Best-consist
目录
摘要 I
Abstract II
1 引言 1
1.1 玻璃陶瓷的概念和应用 1
1.2 白光LED的发展 1
1.3 白光LED用荧光粉合成的现状 2
1.4 本课题的研究意义和内容 2
2 实验过程 4
2.1 实验试剂和设备 4
2.1.1 实验试剂 4
2.1.2 实验设备 4
2.2 溶胶-凝胶法制备荧光粉 5
2.2.1 样品的成分计算和分组 5
2.2.2溶解样品 5
2.2.3 在氧化镓溶液中加入稀土离子和六水合氯化镁 6
2.2.4 调节PH值 6
2.2.5 溶胶 6
2.2.6 室温凝胶 6
2.2.7 样品烘干 6
2.2.8 退火处理 7
2.3 样品检测 7
2.3.1 XRD检测 7
2.3.2 荧光光谱检测 7
3、结果与讨论 8
3.1 XRD结果分析 8
3.2 MgO-Ga2O3-SiO2:Eu3+的荧光光谱分析 10
3.3 MgO–Ga2O3–SiO2:Dy3+的光谱分析 14
4、结论 18
参考文献 19
致谢 21
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