二氧化钛纳米粒子局域等离子体共振增强YAG荧光粉发光特性研究  

Significantly Improved Luminescence Properties of YAG Phosphor via Localized Surface Plasmon Resonance of Nanotitania

作　　者：冯爱明 王富强 张宏 安鹏[2] 李旸晖 王乐[1] FENG Ai-ming;WANG Fu-qiang;ZHANG Hong;AN Peng;LI Yang-hui;WANG Le(College of Optics and Electronic Science and Technology,China Jiliang University,Hangzhou 310018,China;School of Electronic and Information Engineering,Ningbo University of Technology,Ningbo 315211,China;State Key Laboratory of Modern Optical Instrumentation,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]中国计量大学光学与电子科技学院,浙江杭州310018 [2]宁波工程学院电子与信息工程学院,浙江宁波315211 [3]浙江大学现代光学仪器国家重点实验室,浙江杭州310027

出　　处：《光谱学与光谱分析》2020年第10期3081-3085,共5页Spectroscopy and Spectral Analysis

基　　金：国家重点研发计划项目(2017YFB0403100,2017YFB0403105);国家自然科学基金项目(61575182,51832005);浙江省杰出青年科学基金项目(LR19F050001);浙江省科技计划项目(2018C37042)资助。

摘　　要：白光LED具有绿色节能、超长寿命、安全可靠等优点,作为新型照明光源的重要发展方向,如何提高白光LED的发光效率仍是照明领域的核心问题之一。商业中白光LED主要采用蓝色LED芯片激发黄色YAG荧光粉的方式来实现白光,显然提高荧光粉的发光效率将可有效改善白光LED的性能指标。而目前研究较多有关LED用荧光粉的基质创新和掺杂方面,对基于局域等离子体共振效应的荧光粉研究尚有待进一步探索。以钛酸四丁酯为前驱体,采用溶胶-凝胶法制备了以YAG∶Ce^3+荧光粉为载体的表面包覆锐钛矿型纳米二氧化钛的复合荧光材料,研究了TiO 2纳米颗粒包覆YAG∶Ce^3+荧光粉对粉体发光性能的影响。利用X-射线衍射仪、扫描电子显微镜、荧光光度计和拉曼光谱仪等测试手段对样品的物相结构和光学特性进行表征分析。研究结果表明,在不同温度和不同TTBO∶H 2O体积比条件下,制备得到的TiO 2包覆YAG∶Ce^3+荧光粉对粉体的荧光光谱产生了显著的影响,当TTBO∶H 2O=2∶1和煅烧温度600℃时,制备出了发光性能优异的TiO 2包覆YAG∶Ce^3+荧光粉。通过测试分析发现,样品中TiO 2纳米粒子较好的包覆在YAG∶Ce^3+荧光粉表面,锐钛矿衍射峰值相对强度较为突出,锐钛矿具有比金红石更高的光催化活性,高含量的锐钛矿在激发光激发下更加容易产生光生e-和h+;通过拉曼测试表明,在1264.10和1283.59 cm^-1处的特征峰得到了增强,这归因于TiO 2作为一种具有局域等离子体效应的纳米颗粒,在633 nm激发光激发下,激发光频率与TiO 2包覆YAG∶Ce^3+颗粒界面处的电子吸收峰接近,其界面处产生了LSPR效应;通过PL光谱测试分析表明,局域表面等离子体共振效应使得制备的TiO 2包覆YAG∶Ce^3+荧光粉的发光强度提高了21%,量子效率提高了5.5%。研究表明,基于TiO 2的局域表面等离子体效应能有效地提高YAG∶Ce^3+荧光粉的发光�White light-emitting diodes(wLEDs)have been considered to be new-generation light sources due to their advantages such as energy-saving,environment-friendly and long lifetime,safety and reliability.Nevertheless,it is the core issue to improve the luminous efficacy of wLED and excavate lighting properties in depth.At present,the commercial way to produce wLEDs are combining a blue-chip with yellow phosphor material as YAG∶Ce^3+,and the luminescence efficiency of white LED can be effectively improved by improving the luminescence efficiency of phosphor.A novel nanocomposite powder of YAG∶Ce^3+coated with anatase nanotitania particles was prepared by sol-gel method using tetrabutyl titanate as the precursor,and the effect of TiO 2 nano-particles coating on the luminescence properties of YAG∶Ce^3+phosphors were investigated.The phase structure and optical properties of the samples were characterized by X-ray diffractometer,scanning electron microscope and spectrometer.The results have revealed that TiO 2 coating YAG∶Ce^3+phosphors prepared at different temperatures and different volume ratios(TTBO∶H 2O)have a significant effect on the fluorescence spectrum of the powder,optimizing preparation temperature is 600℃and TTBO∶H 2O=2∶1(in volume ratio).The result of the tests showed that TiO 2 coating layer around the phosphor surface by the SEM observation,the diffraction peak of anatase is relatively strong,and the separation of the photogenerated e-/h+pairs can be promoted,leading to increasing quantum efficiency.The Raman spectrum indicated that the energy of localized surface plasmon resonance(LSPR)propagating on the interface at the excitation wavelength of 633 nm,and the intensity of the characteristic peaks at 1264.10 and 1283.59 cm^-1 were increased.The photoluminescence spectrum indicated that luminescence intensity of TiO 2 coating YAG∶Ce^3+phosphors were improved 21%,the quantum efficiency has been improved 5.5%,which was by the contribution of the TiO 2 localized surface plasmon resonance effe

关 键 词：纳米二氧化钛 YAG∶Ce^3+荧光粉 局域等离子体共振 发光效率 

分 类 号：TQ174[化学工程—陶瓷工业]