浅谈我国稀土荧光材料市场

荧光材料主要用于照明、显示和特种需要中的应用,通常利用紫外光子或电子激发荧光材料,使电子激发到高能态,电子从高能态跳回到低能态,其能量以可见光的形式发射出来。这种发光形式不同于高温热发射,因此发光效率高,发光波长在可见光380nm-700nm范围内可调,广泛用于节能、照明和显示行业,如各类照明灯具、电视电脑显示屏、电子广告屏、LED固态照明都要用到稀土发光材料。     

稀土发光材料（研究报告摘要）

稀土发光材料品种多、应用面广，已知的稀土发光材料品种达到300种以上。按应用领域，可大致分为1)显示用稀土发光材料，主要包括阴极射线管(CRT)用荧光粉、投影管用荧光粉、等离子显示(PDP)用荧光粉、场发射显示(FED)用荧光粉等；2)照明用稀土发光材料，主要包括灯用稀土三基色荧光粉、白光发光二极管(白光LED)用荧光粉、稀土卤化物发光材料等；     

红色长余辉发光材料Sr_5Al_2O_7S∶Eu~(2+)的制备及发光性能

以工业铝酸钠溶液制备的氢氧化铝为原料,采用高温固相反应法合成了Sr5Al2O7S∶Eu2+红色长余辉材料。用X射线衍射仪及荧光分光光度计对材料的物相及光谱性能进行了分析,考察稀土掺杂量对样品发光性能的影响。结果表明,在稀土激活剂的掺杂量x(Eu)=6%、硼酸加入量9%、1 200℃烧结8h的条件下合成的样品为Sr5Al2O7S∶Eu2+的纯相,激发光谱位于400～500nm,主发射波长在600nm左右,余辉为桔红色。     

稀土MOF发光调色板和高等级防伪条形码材料

<正>MOF(metal-organic framework,金属-有机骨架)是由金属和有机配体组成的骨架材料,是一类新型的多孔材料。简单的来说MOF就是由金属离子或金属和氧原子、羟基、羧酸等组成的团簇与有机配体结合而成的框架材料。而稀土MOF兼具了有机配体与稀土离子的发光特性,增加了发光形式的多样性和可调性,在OLED(Organic Light-Emitting Diode,有机发光半导体)发光材料与器件、化学传感器、生物功能材料、防伪与显示材料等诸多方面有着广     

上转换发光晶体β-NaYF_4∶Yb~(3+),RE~(3+)的合成方法研究进展

稀土上转换发光晶体在近红外光的激发下能够发出可见光,化学组成为β-NaYF_4∶Yb~(3+),RE~(3+)(RE=Tm,Ho和Er)的晶体是发射绿色、蓝色和红色可见光的最佳材料。综述了用水热法、热分解法和有机溶剂热法合成稀土上转换发光晶体研究现状,系统阐述了各种方法有机试剂、前驱体摩尔比、掺杂Gd~(3+)、反应温度和时间等条件对β相上转换晶体形貌和粒度的影响,并对在生物医学领域应用的粒度10 nm的核壳型上转换发光晶体合成方法以及拓展其应用领域进行了展望。     

铈钴铜铁永磁材料

铈钴铜铁[Ce(Co_(1-x-y)Cu_xFe_y)_5]永磁材料乃稀土永磁材料之一。其磁性能比铝镍钴和铁氧体高得多。一般B_r=6000～7000GS,H_c=4000～4500Oe,(BH)_(max)=9～12MGOe,在稀土永磁中属中等磁性能。由于它采用了廉价的铈、铜、铁代替了Sm(Pr)Co_5中的钐(镨)和部分钴,因而成本低,售价仅为Sm(Pr)Co_5的三分之一,是一种有发展前途的稀土永磁。由于此种材料的磁性能适中,价格低廉,因而已广泛应用于磁选机、磁性泵、发电机、电动机、电子钟、电子手表及各种音响     

稀土在热浸镀铝中的行为和分布研究

分别在工业纯铁和20碳钢上制备了热浸镀纯铝和稀土铝镀层,采用扫描电镜(SEM)观察了镀层横截面和表面的形貌,采用能谱仪(EDS)和电子探针(EPMA)分析了镀层横截面的稀土分布.结果表明,添加稀土热浸镀铝后,表面层厚度减少,合金层厚度增加;镀层表面比较平整、连续、无裸露点、裂纹和氧化物夹杂,且FeAl3相短而细小;稀土渗入了镀层,且分布很不均匀,在部分区域存在偏聚,表面层与合金层界面处以及齿状Fe2Al5相的边缘处和齿尖处稀土含量较高.分析了稀土对镀层厚度和组织形貌的影响及稀土的渗入机理.     

稀土发光性能研究及其应用

对稀土的发光类型进行了简要阐述,对不同发光类型的发光原理进行了论述,并介绍了稀土发光材料在照明显示、无机离子和生命分析检测及矿物分析等领域中的应用,最后对我国稀土材料研究的未来发展提出总结与展望.     

稀土Ce3+/Eu2+激活深红及近红外发光材料的研究进展

深红(650 nm～700 nm)及近红外光(700 nm～1700 nm)已经在诸多领域得到广泛应用。通用照明领域，加入深红光发光材料的荧光转换型白光发光二极管(pc-wLEDs)不仅可以提升显色指数，降低色温，还能使pc-wLEDs的发射光谱适应人眼敏感区域，实现精确的色彩再现。另外，在植物生长以及农业照明领域，深红光发光材料不仅可以实现农作物增量增产还可以降低其对种植环境的依赖程度，实现室内种植。近红外光基于其高穿透力可以在无接触条件下对人体进行无损的生物传感以及生物成像。利用这种高穿透能力以及人体内不同成分对近红外光的吸收差异可以对人体健康指标进行监测。除此以外，近红外光在食品成分和新鲜度分析、夜视、军事、光纤通讯等领域均有着广泛的应用。然而，多领域的应用同样意味着对深红/近红外发光材料性能方面有更高的要求。本文详细介绍了近年来Ce³⁺/Eu²⁺激活的深红/近红外发光材料的研究进展，探讨了其背后的发光机理以及发展趋势，并且总结优势，指明不足，为今后研发高效深红/近红外发光材料提供经验与帮助。     

稀土掺杂Sr2MgSi2O7长余辉发光材料的研究进展

硅酸镁锶(Sr2MgSi2O7)作为目前常用的一种长余辉发光材料基质,性能稳定,耐酸碱性能良好。本文介绍了长余辉发光材料的发光原理,综述了近年来Sr2MgSi2O7长余辉发光材料的主要制备方法以及稀土掺杂Sr2MgSi2O7材料的研究进展,并对该材料的发展做出了展望。制备Sr2MgSi2O7长余辉发光材料的方法主要包括高温固相法,溶胶-凝胶法,化学沉淀法和燃烧合成法,其中最常用的为高温固相法。通过掺杂稀土离子可以形成具有不同发光特性的长余辉发光材料。稀土掺杂Sr2MgSi2O7材料作为一种储能、节能的长余辉发光材料,展现出了广阔的发展和应用前景。     

铝酸锶长余辉材料制备新工艺及发光机理

活化Al-Sr合金粉末水解得到Al（OH）3和Sr（OH）2复合粉末,将其作为长余辉材料的前驱体,采用高温固相反应法制备出Eu、Dy共掺杂的SrAl2O4长余辉材料.利用XRD,SEM,XPS和EDS等技术对Al（OH）3和Sr（OH）2复合粉末的组成和微观结构进行了研究,同时测定了长余辉发光材料的的荧光特性和余辉性能.实验结果表明：前驱体中Al 、Sr在微观状态下分布均匀,有效增大固相反应物之间的接触面积,缩短扩散路径,增大反应速率,降低烧结温度,提高长余辉材料荧光性能.同时利用缺陷化学的基本理论和原则,分析了稀土元素掺杂所生成缺陷对发光性能的影响,改进了长余辉材料空穴转移发光机理模型.     

SrAl2O4:Eu, Dy Nanometer Phosphors Synthesized by Combustion Method

SrAl2 O4: Eu, Dy nanometer phosphors were synthesized by combustion method at 500 ～ 900℃, followed by heating the combustion sample at 1150℃ at a weak reductive atmosphere and nanometer phosphor with much better luminescent properties was obtained. The influences of the initiating combustion temperature, H3BO3 quantity, the mass ratio of urea and nitrate on the luminescent intensity of nanometer phosphors were studied. The optimum synthetic conditions were determined. The analysis results by transmission electron microscopy (TEM) indicate that the particle size of the synthetic product is less than 75 nm. The luminescent materials do not need to be ground. Their coating can be refined. It supplies a new approach to the rapid preparation of the luminescent materials at low temperature. The excitation and emission spectra indicate that the main peaks in the excitation and emission spectrum of nanometer phosphor synthesized by combustion method shifted to the short wavelength compared with the phosphor obtained by the solidstate reaction synthesis method. The reason of blue shift was explained. The afterglow decay results indicate that the decay speed of the afterglow for nanometer phosphor is faster than that obtained by the solid-state reaction method.     

Photoluminescence Characteristics of Gd2Mo3O9 ： Eu Phosphor Particles by Solid State Reaction Method

Eu^3＋-doped Gd2Mo3O9 was prepared by solid-state reaction method using Na2CO3 as flux and characterized by powder X-ray diffractometry. According to X-ray diffraction, this material belonged to a tetragonal system with space group I41/α. The effects of flux content and sintering temperature on the luminescent properties were investigated with the emission and excitation spectra. The results showed that flux content and sintering temperature had effects on the luminescent properties, the optimized flux content and the best temperature was 3 % and 800 ℃ respectively. The excitation and emission spectra also showed that this phosphor could be effectively excited by C-T band （280 nm）, ultraviolet light 395 nm and blue light 465 nm. The wavelengths at 395 and 465 nm were nicely fitting in with the widely applied output wavelengths of ultraviolet or blue LED chips. Integrated emission intensity of Gd2Mo3O9 ： Eu was twice higher than that of Y2O2S ： Eu^3 ＋ under 395 nm excitation. The Eu^3＋ doped Gd2Mo309 phosphor may be a better candidate in solid-state lighting applications.     

Fabrication and luminescent properties of red phosphor M3BO6:Eu3+（M=La,Y）

A series of red phosphors M3BO6:Eu3+(M=La,Y) were synthesized at 1150 oC by conventional solid state reaction method and their luminescent properties were investigated.Structural characterization of the luminescent materials was carried out with X-ray powder diffraction(XRD) analysis.Photoluminescence measurements indicated that the La3BO6:Eu3+ phosphor exhibited bright red emission centered at about 612 nm 626 nm under UV excited.La3BO6:Eu3+ phosphor had better luminescent intensity than Y3BO6:Eu3+ phosphors under the same excitation and measuring conditions.It was shown that the 0.08 mol.% Eu3+ ions in La3BO6:Eu3+ phosphors was optimal.The color parameter indicated that La3BO6:Eu3+ phosphor was a preferable red phosphor for white LED.     

Synthesis and Luminescent Properties of GdAlO3:RE by Combustion Process

Pure GdAlO3: RE (RE = Eu, Pr or Tb) crystalline phase was formed at 900 ℃ with the precursor prepar by nitric-citric combustion process. The synthesis process was studied by XRD, TG-DSC and IR spectra. The analysis results show that there are three main stages in combustion process: ( 1 ) water evaporation and organic compound pyrolysis; (2) combusting reaction; (3)pure crystal formation. GdAlO3: RE powder shows good luminescent properties under 254 nm excitation and was proved to be a good kind of phosphors.     

Luminescent properties and application of Eu3+ -activated Gd2(MoO4)3 red-emitting phosphor with pseudo-pompon shape for solid-state lighting

Eu3+ -activated Gd2(MoO4)3 pseudo-pompon-like red-emitting phosphors were prepared by solid-state method.The structure,morphology,and luminescent properties of these powder samples were investigated by X-ray diffraction (XRD),scanning electron microscopy(SEM),and fluorescent spectrophotometry,respectively.The as-obtained phosphors were single crystalline phase with orthorhombic unit cell.The particles of the powder samples had the length of 5-12 μm and width of 3-7 μm with flake shape and large surface area,which is suitable for manufacture of white LEDs.The phosphor could be efficiently excited by the incident light of 348-425 nm,well matched with the output wavelength of near-UV (In,Ga)N chip,and re-emitted an intense red light peaking at 615 nm.By combing this phosphor with a～395 nmemitting (In,Ga)N chip,a red LED was fabricated,so that the applicability of this novel phosphor to white LEDs was confirmed.It is considered to be an efficient red-emitting conversion phosphor for solid-state lighting based on (In,Ga)N LEDs.     

红色荧光粉La2O3：Eu3＋的合成及发光性质

利用复合沉淀法制备了性能稳定的红色荧光粉La2O3：Eu3＋,同时研究了煅烧温度及掺杂Eu3＋浓度对La2O3：Eu。’发光性能的影响．通过X射线粉末衍射（XRD）和扫描电子显微镜（SEM）来表征荧光粉的晶体结构和颗粒大小及形貌：用激发光谱和发射光谱以及荧光衰减曲线来袁征荧光粉的荧光性能．结果表明：煅烧温度在900℃时,所制备样品为六方晶系La2O3：Eun;SEM图显示掺杂Eu0＋含量为5％的La2O3颗粒直径为15μm左右．最大发射波长和激发波长分别为626nm和396nm,发射光谱中596nm和626nm的发射峰对应的是Eu3＋离子的0D—F1和5D—F2跃迁,其荧光寿命为0．754ms．     

稀土对等离子束表面冶金涂层组织的影响及热力学分析

 采用直流放电压缩电弧等离子束表面冶金技术,在Q235钢表面制备了添加混合稀土氧化物的铁基合金涂层,研究了稀土对等离子束表面冶金涂层组织的影响。结果表明：添加适量的混合稀土氧化物可有效改善冶金涂层的组织和性能。另外,采用热力学方法,分析了稀土氧化物对冶金层中夹杂物的变质作用。分析结果表明：在冶金熔池中,稀土氧化物(Ce2O3)可以被碳还原为稀土元素,这些稀土元素与氧、硫反应生成稀土硫氧化物,起到脱氧、脱硫和净化熔池的效果,从而抑制冶金层中凝固裂纹的形成。     

Photoluminescent properties of Ca2Gd8(SiO4)6O2: Dy3+ phosphor films prepared by sol-gel process

There are growing interests on phosphor thin films owing to their potential application in high-resolution devices such as cathode ray tubes and flat panel display devices. The solution-based sol-gel method is one of the most important techniques for the synthesis of vari-ous functional coating films. Compounds with the apatite structure are very suitable host lattices for various luminescent ions. Ca2RE8(SiO4)6O2 ( RE=Y, Gd, La ) is a kind of ternary rare-earth-metal silicate with oxyapatite structure, which has been used as host mate-rial for the luminescence of various rare earth and mercury-like ions. In this article, Ca2Gd8(SiO4)6O2:Dy3 phosphor films were dip-coated on quartz glass substrates through the sol-gel process. X-ray diffraction (XRD), atomic force microscopy (AFM), photoluminescence (PL) spectra, as well as lifetimes were used to characterize the resulting films. AFM study revealed that the phosphor films consisted of homoge-neous particles. The Dy3 showed its characteristic emission in crystalline phosphor films, i.e., 4F9/2–6H15/2 and 4F9/2–6H13/2.     

Study on Ca8Mg(SiO4)4Cl2:Eu2+ Doped with Sr2+

Ca8Mg(SiO4)4Cl2:Eu2 phosphor doped with Sr2 cation for Ca2 partially, was synthesized by solid-state reaction at high temperature under reducing atmosphere, and its luminescent properties were investigated. The experimental results indicate that the emission intensity of the phosphor increases after being doped with a few amount of Sr2 ion. The emission peak of the phosphor blue shift to about 464 nm when the phosphor is doped with large quantity of Sr2 ions. The excitation spectrum indicates that the phosphor can be well excited by UV and blue light from 300 to 460 nm, and the phosphor was fitted well for the excitation by UV or blue-LED.