论文总字数：32017字

摘 要

近红外光源可广泛应用于光通信，生物医学成像，光谱学，食品检测，安全监控和面部识别等各种领域。固态照明技术的快速发展为开发荧光转换型近红外LED作为新型近红外光源提供了可能性。该新型LED由近红外荧光粉和InGaN蓝色LED芯片组合而成，具有可调节的宽发射光谱、热稳定性好、价格低廉、功率高、节能环保等优势，具有广阔的市场应用前景。本课题采用高温固相法合成了Cr³ 单掺杂、Cr³ - Nd³ 共掺杂以及Cr³ - Nd³ -Yb³ 共掺杂的YAl₃(BO₃)₄荧光粉，研究了制备工艺和化学成分对荧光粉晶体结构和发光性能的影响。主要研究结果如下：

1. YAl₃(BO₃)₄基荧光粉最佳的制备条件为H₃BO₃过量20%，1250℃烧结10h；Cr³ 单掺杂、Cr³ - Nd³ 共掺杂YAl₃(BO₃)₄荧光粉均可以被蓝光高效激发，其中YAl_2.88Cr_0.12(BO₃)₄荧光粉可发射650~850nm的深红光和近红外光，Y_0.99Al_2.88(BO₃)₄：0.12 Cr³ ，0.01Nd³ 荧光粉可发射890nm的近红外光，可以用来构建单波段近红外LED。
2. Y_0.98Al_2.88(BO₃)₄：0.12Cr³ ，0.01Nd³ ，0.01Yb³ 荧光粉在蓝光激发下可发射690nm~850nm， 890nm和980nm的近红外光，可以用来构建多波段近红外LED器件；荧光寿命衰减曲线证明了Cr³ - Nd³ 间，Cr³ - Nd³ -Yb³ 间存在着有效的能量传递。
3. 以上三种荧光粉均具有优异的热稳定性，在200℃时，仍然保持90%以上的相对发光强度，可以满足LED器件的高温工作环境，在宽带近红外荧光转换型LED的应用中具有很大的潜力。

关键词：近红外LED；荧光粉；YAl₃(BO₃)₄；Cr³ ；Nd³ ；Yb³

Abstract

Near-infrared light sources can be widely used in various fields such as optical communication, biomedical imaging, spectroscopy, food testing, security monitoring, and facial recognition. The rapid development of solid-state lighting technology has provided possibilities for the development of fluorescence-converted near-infrared LEDs as novel near-infrared light sources. The new kind LED is composed of a combination of near-infrared phosphor and InGaN blue LED chip. It has the advantages of wide adjustable emission spectrum, good thermal stability, low price, high power, energy saving and environmental protection, etc., and it has broad market application prospects.

In this project, a series of Cr³ single-doped, Cr³ -Nd³ co-doped and Cr³ -Nd³ -Yb³ co-doped YAl₃(BO₃)₄ phosphor are synthesized by high temperature solid state method. The effects of preparation process and chemical composition on the crystal structure and luminescent properties of phosphors are studied. The main results of the study are as follows:

1. The optimal preparation conditions of YAl₃ (BO₃) ₄ based phosphors are 20% excess of H₃BO₃ and sintering at 1250°C for 10 hours; both Cr³ single-doped and Cr³ -Nd³ co-doped YAl₃ (BO₃) ₄ phosphors can be efficiently excited by blue light. Furthermore, the YAl_2.88Cr_0.12(BO₃)₄ phosphor can emit deep red light and near-infrared light from 650 to 850 nm,Y_0.99Al_2.88(BO₃)₄:0.12 Cr³ ,0.01Nd³ can emit near-infrared light at 890 nm, which can be used to construct single-band near-infrared LEDs.
2. The Y_0.98Al_2.88(BO₃)₄:0.12 Cr³ ,0.01Nd³ ,0.01Yb³ phosphors can emit near-infrared light at 690nm~850nm, 890nm and 980nm under blue light excitation, and can be used to construct multi-band near-infrared LED devices; the fluorescence lifetime decay curve proves that there is an effective energy transfer between Cr³ -Nd³ and Cr³ -Nd³ -Yb³ .
3. The above three phosphors all have excellent thermal stability and still maintain relative luminescence of over 90% at 200°C. The strength can meet the high temperature working environment of LED devices, and has great potential in the application of broadband near-infrared fluorescence conversion LEDs.

KEY WORDS: Near-infrared LED; phosphors; YAl₃ (BO₃)₄; Cr³ , Nd³ , Yb³

目 录

摘要 I

Abstract II

第一章 绪论 1

1.1 红外LED简介 1

1.1.1 LED简介 1

1.1.2 近红外光的特点及应用 1

1.1.3 蓝光LED激发近红外荧光粉 2

1.2 近红外荧光粉的研究现状 2

1.2.1 近红外荧光粉概述 2

1.2.2 YAB荧光粉简介 3

1.2.3 Cr³ 掺杂荧光粉 4

1.2.4 稀土离子Nd³ 、Yb³ 掺杂荧光粉 4

1.3 近红外荧光粉的制备方法 5

1.3.1 高温固相法 5

1.3.2 溶胶-凝胶法 5

1.3.3 水热合成法 5

1.3.4 共沉淀法 6

1.4 本文的研究目的和主要研究内容 6

第二章 样品制备与分析测试 7

2.1 实验原料 7

2.1.1 实验试剂 7

2.1.2 实验仪器 7

2.2 样品制备 7

2.2.1 荧光粉前驱体粉末原料配制 7

2.2.2 荧光粉制备 8

2.3 实验分析测试方法 8

2.3.1 X射线粉末衍射 8

2.3.2 荧光光谱分析 8

2.3.3 荧光热稳定性测试 8

2.3.4 荧光寿命分析 9

第三章 Cr³ 掺杂YAl₃(BO₃)₄近红外荧光粉的制备和性能研究 10

3.1 Cr³ 掺杂量对荧光粉性能的影响 10

3.2 硼酸过量度对荧光粉性能的影响 12

3.3 助熔剂对荧光粉性能的影响 13

3.4 荧光粉的热稳定性分析 14

3.5 本章小结 15

第四章 Cr³ ，Nd³ 共掺杂YAl₃(BO₃)₄近红外荧光粉的制备和性能研究 16

4.1 YAl₃(BO₃)₄：Cr³ , Nd³ 的物相分析 16

4.2 YAl₃(BO₃)₄：Cr³ , Nd³ 的发光性能及能量传递机理 16

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