PDP用蓝色荧光粉的研究进展

综述了近年来等离子体平板显示器(PDP)用蓝色荧光粉的研究进展,介绍了PDP蓝色荧光粉的种类和制备方法,分析了现有PDP蓝色荧光粉存在的问题和不足,并展望了PDP蓝色荧光粉未来的发展趋势。     

PDP蓝色荧光粉BaMgAl10O17:Eu2+研究现状与前景

彩色等离子体平板显示(PDP)是信息显示领域重要发展方向之一,荧光粉对PDP性能起决定性的作用,红色、绿色荧光粉体技术相对成熟,蓝色荧光粉研究滞后,问题也比较多.概述了BAM蓝色荧光粉体的结构、发光机理、制备工艺、劣化机理,并提出了BAM荧光粉体研究的技术前景.     

PDP红色荧光粉的制备动态

阐述了现有PDP红色荧光粉存在的问题,并重点从改进生产工艺和制备纳米级红色荧光粉对近几年改善PDP红色荧光粉质量的相关研究工作进行了阐述.     

中科院应化所PDP荧光粉取得创新性成果

北京有色金属研究总院、中科院长春应化所、中科院光机与物理所、有研稀土新材料股份有限公司经多年的联合攻关，突破了彩色等离子显示屏（PDP）用荧光体产业化关键技术，开发出了具有我国独立知识产权的PDP用高效荧光粉，所得产品主要性能达国际先进水平。     

彩色PDP纳米荧光粉的研究

等离子体显示(PDP)具有超薄、高清晰、大画面等优点而被世界公认是实现壁挂式高清晰度电视(HDTV)的首选技术,而荧光粉对PDP性能起着决定性作用.着重介绍了纳米PDP荧光粉的制备方法及影响发光性能的关键因素,并提出了其研究的技术前景.     

彩色PDP纳米稀土荧光粉Zn2SiO4:Mn,Er的制备与性能研究

利用溶胶-凝胶法结合超声波分散技术,制备了适用于彩色PDP的绿色纳米荧光粉Zn2SiO4:Mn,Er,同时对样品的后处理等一系列影响其性能的因素进行了讨论.此方法极大地节省了反应时间,所得荧光粉的色坐标x=0.2246,y=0.6984;平均粒度为50nm,相对发光强度达467.4.     

SMPDP放电单元中荧光粉层对放电特性的影响

本采用流体模型，计算了新型荫罩式PDP(SMPDP)放电单元的放电特性。研究了放电单元中荧光粉层的厚度对放电过程和着火电压的影响。模拟结果表明，在SMPDP结构中，荧光粉层厚度的变化，对放电过程的影响小于通常的表面放电型，PDP(ACC PDP)。最低着火电压随荧光粉层厚度的不同变化较小。因此，SMPDP结构中，荧光粉层涂敷的不均匀性对放电均匀性的影响小于ACC PDP结构。     

PDP用红色荧光粉的研究进展

简要介绍了目前研究和使用的PDP用红色荧光粉的研究现状,综述了国内外PDP用红色荧光粉的合成研究进展,最后展望了PDP用红色荧光粉的发展前景.     

PDP用高亮度(Y,Gd)BO_3:Tb~(3+)绿色荧光粉的合成

采用共沉淀法制备了稀土氧化物前体,再将其和H3BO3及BaB4O7混合后,用高温固相合成法制备出了2.0-3.0μm粒径的(Y,Gd)BO3:Tb3+绿色荧光粉。研究发现,荧光粉的粒度随前驱体粒度与助熔剂引入量的增加而增大,助熔剂的引入量超过0.18%会使荧光粉的亮度猝灭;随着灼烧温度的增高,荧光粉的亮度会变大。综合PDP用荧光粉的使用特性,BaB4O7的引入量在0.10%,灼烧温度为1100℃时,采用共沉淀法前驱体可得到亮度104,粒度2.5um,晶型完美的(Y,Gd)BO3:Tb3+绿色荧光粉。     

白色发光二极管用蓝色荧光粉的研究进展

白色发光二极管(WLED)被称为第四代照明光源,应用前景十分广阔.概速了目前国内外WLED用蓝色荧光粉的研究进展,介绍了WLED用蓝色荧光粉的基质材料、制备方法、发光中心和掺杂离子等对WLED用蓝色荧光粉发光性能的影响,展望了该类荧光材料的发展研究趋势和应用前景.     

Use of LiF flux in the preparation of Ca3Sc2Si3O12:Ce3+ phosphor by sol-combustion method

LiF flux was added when prepare Ca₃Sc₂Si₃O₁₂:Ce³⁺ phosphors with sol-combustion method using urea as a fuel and chelating agent. Investigation of phase, morphology and photoluminescence of the phosphors reveals that this kind of method can decrease the phase-forming temperature by 400–500 °C and the phosphors show more uniform morphology and more excellent photoluminescence properties compared to conventional solid-state method. As one of the most important parameters for phosphors used in white light emitting diodes, the thermal quenching properties of the prepared samples are compared and discussed. The fabrication of single-color light emitting diodes show the Ca₃Sc₂Si₃O₁₂:Ce³⁺ phosphor prepared by sol-combustion method with LiF flux can be considered as a more promising high efficiency candidate used for white light emitting diodes than the phosphor made by solid-state method.     

A review of X-ray imaging phosphors

The important methods of X-ray imaging use various phosphors. The phosphors give light proportional to the amount of radiation. The light is emitted either as X-ray excited fluorescence, phosphorescence, or due to stimulated, radiative recombinations of defects generated by X-ray exposures. The role of phosphors in improving image quality and reducing exposures to patients is important. Properties of various phosphors which can be used for X-ray imaging applications are reviewed here.     

La0.8Y0.2PO4∶Bi3+ ，Sm3+ ，Eu3+ 荧光粉的合成,性能及其前驱体热分解动力学

相对于绿色和蓝色荧光粉,红色荧光粉因不能有效吸收近紫外光,致使发射的红光强度不能与蓝、绿两种荧光粉的发光强度同步,影响了其显色性,降低了发光效率.为获得能够被近紫外光高效激发的红色荧光粉,本文以硝酸铕、硝酸钐、氯化铋、氧化镧、氧化钇、磷酸三铵为原料,经高温固相反应合成得到Bi,Sm,Eu掺杂磷酸镧钇荧光粉,利用XRD,SEM,荧光光谱及TG/DTG对产物进行了表征,并采用非等温法研究前驱体的热分解过程,进而探究前驱体热分解反应过程的动力学及焙烧过程中荧光粉的形成机理.研究表明:Bi3+的最佳掺杂浓度为x=0.03,所得产物为以磁偶极(5D0→7F1)跃迁为主导发射的红色荧光粉;最佳产物与未掺杂产物相比,前者的荧光强度是后者的2.66倍;最佳产物前驱体的热分解过程只有一步失重,经计算获得了该过程对应的活化能、机理函数及指前因子.Bi,Sm,Eu掺杂磷酸镧钇荧光粉是一种发光效率高、具有广泛应用前景的近紫外激发白光LED用红色荧光粉.     

Comparative study of Ca3Bi(PO4)3:Eu3+ phosphors prepared by three methods

Ca₃Bi(PO₄)₃:Eu³⁺ phosphors were synthesized by solid-state (SS) reaction, co-precipitation (CP) and sol–gel methods. The resulting phosphors were well characterized by X-ray diffraction, field-emission scanning electron microscopy and photoluminescence spectra. The X-ray diffraction results suggested that the pure phase of Ca₃Bi(PO₄)₃:Eu³⁺ can be obtained by SS reaction and CP method. The phosphors obtained by CP method showed more homogeneous, agglomerate-free particles. The samples obtained by the CP method showed the highest emission intensity among the three methods which fired at 1,000 °C for 2 h. It was showed that the CP method was the most respected process for the preparation of Ca₃Bi(PO₄)₃:Eu³⁺ phosphors.     

Deep traps in CaS:Eu and CaS:Ce phosphors

The photoluminescence, thermoluminescence, and excitation spectra of CaS:Eu and CaS:Ce phosphors containing various coactivators were measured. The spectra of deep trapping levels in these phosphors were studied for the first time. Optical information writing and storage effects were found in the UV range for both phosphors and in the visible range for CaS:Eu. The written optical information can be readout by IR irradiation.     

Eu2+掺杂硅基氮氧化物荧光粉的制备与发光特性

为获得接近太阳光的自然发光效果,制备了Eu2+掺杂的硅基氮化物系列荧光粉,并对其发光特性及原理进行研究.采用碳热还原氮化法制备了Eu2+掺杂Sr Si O3-Sr2Si5N8-Sr Si2O2N2红色荧光粉.利用X射线衍射仪(XRD)、荧光分光光度计、MS-CASTEP对产物物相、发光光谱、电子结构进行了测试分析.结果发现:通过调节煅烧工艺参数,可同时获得2种主要物相或者单一物相的荧光粉;所制备的荧光粉,能够在350~400 nm范围内被UVLED很好地激发,根据主晶相的不同,产物的发射光谱可以在400~700 nm波段内调控.采用第一性原理分析了发射峰位于650 nm附近橙红色主晶相Sr2Si5N8∶Eu2+的电子结构和光物理性能,发现该物相为直接带隙半导体材料,Eu2+的4f轨道对费米面电子峰起主要作用.Eu2+掺杂Sr Si O3-Sr2Si5N8-Sr Si2O2N2是优良的、颜色可调控的红色荧光粉材料.     

Combustion synthesis of borate phosphors

A fast and simple method of preparation, based on the combustion synthesis, is described for the synthesis of borate based PL phosphors which can be used for commercial lamp applications. Phosphors with various structures, incorporating different activators could be successfully prepared. PL intensities of (Gd_0.6Ce_0.2Tb_0.2)MgB₅O₁₀, SrB₄O₇:Eu²⁺ and La_0.88Gd_0.1Bi_0.02B₃O₆ were found to be comparable with those of the corresponding commercial phosphors.     

Self heat generating synthesis of tri-colour lamp phosphors

The simple method for the preparation of phosphors such as aluminates, Y₂O₃, YVO₄ and LaPO₄ by the combustion synthesis described earlier in the literature is reported. It is shown here that the phosphors prepared by such synthesis do not possess all the required characteristics. Suitable modifications by way of annealing at >1200°C in controlled atmospheres, however, can yield the phosphors with characteristics which may fulfil the demands of lamp industry.     

白光LED用YAG∶Ce~(3+)发光材料的性能增强研究

以硼酸和碱土氟化物作为助熔剂,调整助熔剂比例和组分,采用高温固相法合成一系列白光LED用YAG∶Ce3+发光材料。采用XRD、扫描电镜(SEM)和荧光光谱(PL)等对样品进行表征。研究表明,合适的助熔剂有助于降低样品的烧结温度,不会有杂相产生,加入不同浓度和成分的助熔剂对样品的发射、激发光谱形状和峰值波长位置无影响,但对发光强度影响较大;采用助熔剂质量分数为0.4%(0.2%H3BO3-0.2%BaF2)时,所合成样品的颗粒比较均匀,发光性能的增强最为有效。将其和蓝光Ga(In)N芯片封装成白光LED,光效也得到显著提高。封装后白光LED的色坐标为(0.3341,0.4190),色温为5470K,显色指数为67,光效可达到78.3lm/W,高于其它条件合成荧光粉封装的白光LED。     

有机半导体照明(有机照明)研究进展

采用有机发光二极管(OLEDs)的有机半导体照明(有机照明)是绿色环保、健康安全的新型面光源,有望在固态照明领域得到广泛的应用。有机照明的发展是随着有机发光材料的不断进步而进步的。有机发光材料从最初的荧光材料发展到磷光材料以及最近提出的热活化延迟荧光材料,其性能在不断地提升。基于这些材料的白光OLEDs的性能也在不断提升。最早的白光器件基于荧光小分子材料,但是由于只能利用单线态激子发光,效率很低。随后磷光材料的引入使得白光器件的效率大幅度提升,但是由于蓝色磷光材料本身的稳定性问题,全磷光白光器件的寿命较短。为了结合荧光和磷光的优点,人们提出了荧光/磷光杂化的白光器件,这是目前最有前景的一类白光器件结构。目前针对有机照明的研究,已从早期只关注效率突破阶段,进入到综合提高效率和寿命阶段。从荧光白光、磷光白光以及荧光/磷光混合白光3个方面对有机照明的研究状况、发展趋势进行了介绍。