Luminescent Properties of Ca2 Y8 ( SiO4 ) 6O2:Eu3 + Phosphors Prepared by Spray Pyrolysis Process

Using CaCO3, metal oxides (all dissolved by nitric acid) and tetraethoxysilane Si (OC2H5 )4 (TEOS) as the main starting materials, Ca2Y8 (SiO4 )6O2: Eu3 phosphors were synthesized by spray pyrolysis.X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectra as well as lifetimes were used to characterize the resulting phosphors.The results of XRD indicated that the 1000 ℃ annealed powders crystallize with the silicate oxyapatite structure.SEM study revealed that the phosphors consist of spherical particles with an average size of about 1 ～ 3 μm.In the crystalline Ca2 Y8 (SiO4)6O2: Eu3 phosphor, the Eu3 shows its characteristic emission corresponding to 5 D0 - 7 FJ ( J = 0, 1,2, 3, 4) transitions, with 5D0 - 7 F2 red emission (613 nm) as the most prominent group, agreeing well with the structure of the host material.     

New Green Phosphors Ba（1-x）SrxZr（BO3）2 Doped with Tb^3＋ for PDP Applications

Thephosphorsusedinplasmadisplaypanel(PDP)deviceshouldemitvisiblelightundervacuum ultraviolet(VUV)excitationof147nmand or172nm fromXe Hegasplasma[1].Recentlylotsoftraditional lampphosphorshavebeenusedascommercialphos phorsforPDP.However,thesematerialsstill…     

Spherical YAG:Ce3+ Phosphor Particles Prepared by Spray Pyrolysis

Spherical YAG:Ce3 phosphor particles with narrow size distribution were prepared by spray pyrolysis. The effects of the concentration of solution, the flow rate of carrier gas and the annealing temperature on the phosphor morphology were studied. The productivity of precursor particles shows a trend of drop after rising with the increase of concentration. Raising the flow rate of nitrogen can improve the productivity of the precursor particles. Phosphor prepared by spray pyrolysis has obviously higher emission intensity than that synthesized by solid state reaction, spray pyrolysis makes Ce3 ions well distributed in the crystal lattice as the luminescent centers, and phosphor particles have regular sphericity and narrow size distribution.     

用喷雾干燥法制备PSZ-3Y粉末颗粒的形貌研究

用激光衍射法和SEM（Scanning Electron Microscope)法研究了喷雾干燥法制备PSZ-3Y粉末的粒度分布和形貌特征，表明用传统法制备的PSZ-3Y虽然可以获得细颗粒粉末，但是团聚非常严重，分散性能和流动性都很差，而用喷雾干燥法制备的PSZ-3Y粉末和造粒可以获得粒度分布均匀，流动性和分散性好的不团聚的球状颗粒。粉末的形貌与其采用的制粉原料的组成形态和工艺关系不大，但从原粉中喷雾制粒获得粉末的颗粒表面较粗糙和有小裂纹，其分布性能比直接喷雾粉末颗粒性能好。     

Synthesis and Electrical Properties of La0.8Sr0.2-xCaxCo0.9Fe0.1O3-δ

Ａｎｉｍｐｏｒｔａｎｔｇｏａｌｉｎｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｓｏｌｉｄｏｘ ｉｄｅｆｕｅｌｃｅｌｌｓ (ＳＯＦＣｓ)ｉｓｔｏｒｅｄｕｃｅｔｈｅｏｐｅｒａｔｉｎｇｔｅｍ ｐｅｒａｔｕｒｅｏｆｔｈｅｆｕｅｌｃｅｌｌｓｔａｃｋｆｒｏｍ 10 0 0℃ｔｏｂｅｌｏｗ85 0℃ｓｏａｓｔｏｇｅｔａｎｏｐｔｉｍｕｍｔｒａｄｅ ｏｆｆｂｅｔｗｅｅｎｐｅｒ ｆｏｒｍａｎｃｅａｎｄｌｉｆｅｔｉｍｅｏｆｔｈｅｓｔａｃｋａｎｄｔｏｒｅｄｕｃｅｔｈｅｏｖｅｒａｌｌｓｙｓｔｅｍｃｏｓｔ[1] .Ｔｏａｃｈｉｅｖｅｔｈｉｓｄｅｓｔｉｎａｔ…     

喷雾干燥吸收工艺处理焚烧烟气的研究

从设计的角度出发,通过对危险废物焚烧工艺实际运行监测结果的分析,以控制脱酸烟气进出口温度、化学计量比、碱性液体浓度和碱性液滴粒径等工艺参数来研究危险废物焚烧烟气的净化效率与上述参数之间的关系。     

喷雾干燥吸收工艺处理焚烧烟气的研究

从设计的角度出发，通过对危险废物焚烧工艺实际运行监测结果的分析，以控制脱酸烟气进出口温度、化学计量比、碱性液体浓度和碱性液滴粒径等工艺参数来研究危险废物焚烧烟气的净化效率与上述参数之间的关系。     

Citrate-Gel Synthesis and Luminescent Properties of α-Zn3(PO4)2 Doped with Eu3+

By using inorganic salts as raw materials and citric acid as complexing agent, α-Zn3(PO4)2 and Eu3 doped α-Zn3(PO4)2 phosphor powders were prepared by a citrate-gel process. X-ray diffraction(XRD), TG-DTA, FT-IR and luminescence excitation and emission spectra were used to characterize the resulting products. The results of XRD reveal that the powders begin to crystallize at 500 ℃ and pure α-Zn3(PO4)2 phase is obtained at 800 ℃. And the results of XRD reveal that Eu3 exists as EuPO4 in the powder. In the phosphor powders, the Eu3 shows its characteristic red-orange(592 nm, 5D0-7F1) emission and has no quenching concentration.     

喷雾干燥回收沉淀泥浆中的TiCl4

采用喷雾干燥法对粗四氯化钛沉淀泥浆中TiCl4的回收进行了研究。首先,在实验室以空气作为沉淀泥浆干燥的加热介质,进行喷雾干燥。然后,在生产现场以氩气作为沉淀泥浆干燥的加热介质,进行喷雾干燥。研究结果表明,以氩气作为沉淀泥浆干燥的加热介质,在喷雾驱动进气压力为0.5 MPa,加热干燥进气压力为0.15 MPa,加热干燥进气温度为350℃,尾气出口温度为125℃的条件下喷雾干燥,沉淀泥浆中TiCl4的含量由55.3%(质量分数,下同)降至1.8%,对应泥浆中TiCl4的蒸发率达98%以上,回收率达96%以上。     

Synthesis and photoluminescence studies of Ba(Gd,Ln)B9O16:Eu3+(Ln=La,Y) phosphors for n-UV LED lighting and display devices

BaGdB9O16:Eu3+ and Ba(Gd,Ln)B9O16:Eu3+(Ln=La, Y) phosphors were synthesized by solid state diffusion method. The X-ray diffraction, scanning electron microscopy(SEM) and photoluminescence properties were investigated. The as-synthesized BaGdB9O16:Eu3+ and Ba(Gd,Ln)B9O16:Eu3+(Ln=La, Y) phosphors showed strong red emission under ultraviolet light excitation. By partially substituting Gd3+ by La3+ and Y3+ ions in the host BaGdB9O16:Eu3+ materials, the maximum emission intensity was observed for the optimum composition of BaGd0.91La0.8B9O16Eu0.01 phosphor. The experimental results indicated that the Eu doped BaGdB9O16 and Ba(Gd,Ln)B9O16(Ln=La, Y) phosphors were promising red phosphors, which might find potential applications in near-UV excited LED lighting as well as display devices. Comparison of as-synthesized phosphors with standard phosphor used in CFL(compact fluorescent lamp) was also done. Energy transfer mechanism of Gd3+ to Eu3+ was also discussed in this paper.     

Synthesis and thermoluminescence properties of rare earth oxides （Y, Ce-Lu） doped lithium triborate

Lithium triborate (LiB3O5) was synthesized by high temperature solid-state reaction method, and then rare earth oxides were doped into LiB3O5 to enhance its thermoluminescent (TL) properties. The identification and characteristics of the obtained compounds were determined by X-ray diffraction (XRD), Fourier transform infrared (FTIR) analyses, differential thermal analyses (DTA) and scanning electron microscopy (SEM). The glow curves were obtained using a thermoluminescent (TL) reader. The results revealed that all the rare earth oxides were not good activators for lithium triborate and the obtained compounds could not be used for dosimetric applications.     

喷雾干燥法制备PSZ—3Y粉末的粒度研究

用激光衍射法和BET法（Brunner-Emmett-Teller Method)研究了用喷雾干燥法制备的PSZ－3Y粉末的粒度性能。用喷雾干燥法能制得粒度均匀性好的球状PSZ－3Y粉末。影响粒度的主要因素是料液中（ZrO2 Y2O3)的浓度,其次是送料速度。从颗粒形貌图看出,颗粒表面布满了裂纹,所以这样的粉末经二次处理后,可获得超细粉末。     

Co-Precipitation Preparation and Luminescent Behavior of (Y,Gd)BO3∶ Eu Phosphor

(Y,Gd)BO3∶ Eu phosphors were prepared by co-precipitation precursors, and luminescent properties were investigated. The precursors were synthesized by introducing hydroxyl ion to mixed solution of rare earth nitrates and boric acid, either through adding ammonia(precursor 1)or through controlled release of hydroxyl ion of urea(precursor 2). The precursors were fired in air at 1000 ℃ for 2 h. Resulted phosphor synthesized with precursor 1 has non-uniformed particle with mean diameter of about 3 μm, while that with precursor 2 exhibits uniformed near spherical-like morphology with mean diameter of about 300 nm. Phosphors with the two methods exhibit same crystal structure as that of commercial one. Emission spectra of the samples indicate that the sample prepared with precursor 2 shows relative higher intensity(exited by 172 nm VUV)than that prepared with the other precursor.     

InBO3:Tb3+荧光粉的合成及其发光性质

硼酸盐体系绿色荧光粉具有发光效率高、光色纯、烧结温度低、合成简便、粒径适中等优点,广泛用于等离子彩色电视机.应用高温固相反应法合成In0.98Tb0.02BO3荧光粉,并研究其中Tb3 的光谱性质及能量传递现象.发现激发光谱中Tb3 在274nm处有一最强4f→5d激发峰,能有效地吸收能量.发射光谱在550nm处有一最强峰,属于Tb3 的5D4→7F的跃迁,发绿光.发射峰高而窄,说明荧光粉In0.98Tb0.02BO3发光强度高,且只有一个峰,说明发光颜色纯,有一定的开发价值.还研究了几种因素对In0.98Tb0.02BO3荧光粉相对亮度的影响并得出了合成In0.98Tb0.02BO3荧光粉的最佳实验条件: 焙烧温度1300℃,焙烧时间4h.     

Red Emitting Phosphor (Y,Gd)BO3:Eu3+ for PDP Prepared by Complex Method

Red phosphor (Y, Gd)BO3:Eu3+ with grain shape, small size, non-agglomerate, high crystallinity and good photoluminescence (PL) intensity was prepared by a complex method that the precursor of the phosphor was prepared by co-precipitation method and the phosphor was prepared by combustion method. The SEM photos and the photoluminescence spectrum excited under VUV show that the morphology and luminescent properties of this phosphor are satisfied when an appropriate amount of urea was adopted as the combustion agent in the preparation procedure.     

Synthesis and Characterization of Cerium-Doped Lutetium Aluminum Garnet Phosphors by Nitrate-citrate Sol-Gel Combustion Process

Nanosized cerium-doped lutetium aluminum garnet （LuAG：Ce） phosphors were prepared by nitrate-citrate solgel combustion process using 1：1 ratio of the citrate：nitrate. The prepared LuAG：Ce phosphors were characterized by XRD, TEM, photoluminescence and radioluminescence spectra excited by UV and X-ray, respectively. The purified crystalline phase of LuAG：Ce was obtained at 900 ℃ by directly crystallizing from amorphous materials. The resultant Lu- AG：Ce phosphors were uniform and had good dispersivity with an average particle size of about 30 urn. Both photoluminescence and radioluminescence were well-known Ce^3＋ emissions located in the range of 470 -600 nm consisting of two emission bands because of the transition from the lowest 5d excited state （2D） to the 4f ground state of Ce^3＋, which matched well with the sensitivity curve of the Si-photodiode. There was a little red shift for the emission components from the UV-excited emission spectrum to the X-ray-excited emission spectrum. The fast scintillation decay component of 26 ns satisfies the requirements of fast scintillators.     

Luminescence Characterization of Mg Doped Y2O2S:Ti Long Afterglow Phosphor

Y1.94-xMgxO2S:0.06Ti (0≤x≤0.10) phosphors with long afterglow were synthesized by solid state reaction route. The photoluminescence spectra, decay curves, thermoluminescent spectra and chromaticity coordinate curves were investigated. The results show that the luminescence intensity of Y1.94-xMgxO2S:0.06Ti (0≤x≤0.10) phosphors decrease gradually with increasing Mg2 ion content, and the shape of luminescence spectra and chromaticity coordinate change as well. Furthermore, two thermoluminescent peaks in single Ti-doped Y2O2S sample are found at 91.8 and 221.5 ℃, respectively. Nevertheless, significant different spectra were found for the Mg, Ti co-doped Y2O2S samples that three thermoluminescence peaks appear at 52.3, 141.7 and 226.8 ℃, respectively. These results indicate that the co-doped Mg ion changes the inherent trap depth of single Ti-doped Y2O2S:Ti phosphor, and induces simultaneously a new trap level in the Y1.94-xMgxO2S:0.06Ti phosphor. Based on the analysis of thermoluminescent spectra, photoluminescent spectra, decay curve and crystal structure defect, it was proposed that the varied structure defect and introduced new trap level by the doped Mg2 ions should be responsible for reducing luminescence intensity and varying color in the Y1.94-xMgxO2S:0.06Ti phosphor.     

Synthesis of Spherical (Y,Gd)BO3∶Eu3+ Phosphor Using W/O Emulsion System

Spherical (Y, Gd)BO3:Eu3 phosphor particles with a narrow size distribution(2～4 μm) was obtained by firing the Y-Gd-Eu-BO3 precursor prepared in a W/O style emulsion system. In the W/O emulsion system, kerosene, used as oil phase, was mixed with Span 80 and Tween 80 compounds which were employed as the emulsifier with an HLB (hydrophile-lipophile balance) value of 5.2～5.3. Both rare earths (Y, Gd and Eu) nitrate and boric acid solution or ammonia solution were used as aqueous phase. The synthesis conditions, such as emulsion composition, emulsifying style, precipitation reaction process, reaction temperature, morphology control, and so on, were investigated, and the optimum synthesis conditions for preparing spherical (Y, Gd)BO3∶Eu3 phosphor was obtained. The phosphor was characterized by XRD, SEM, laser particle size analysis, emission and excitation spectrum under vacuum ultraviolet (VUV), and so on. The phosphor synthesized using the water-in-oil emulsion method with median diameter (D50) of 2～4 μm shows agreeable photoluminescence (PL) property and sphericity. The main emission peak appears at about 593 nm, which corresponds to 5D0→7F1 transition (magnetic-dipole transition) of the Eu3 ion. The cell parameters and powder diffraction data were indexed. The structure of the phosphor belongs to the hexagonal system with space group P63/m.     

稀土金属甲醇盐的制备及表征

以碱土金属钙醇盐为烷氧基提供者,与无水稀土乙酸盐(乙酸镧、乙酸镨、乙酸钕、乙酸钐)在芳香族类溶剂体系中60℃回流加热反应6h～8h,合成出稀土金属(La、Pr、Nd、Sm)甲醇盐。样品红外光谱表明,在1035cm-1左右出现了甲氧基与稀土元素键合的C-O-Ln键的特征吸收峰,紫外-可见谱中出现的三价稀土离子的特征吸收峰,进一步证实了样品为稀土甲醇盐。     

Synthesis and Luminescence Properties of Gd_2O_3∶Eu~(3+) Phosphors

Gd2 O3∶Eu3+ isanefficientredemittinglumines centmaterial ,whichcanbeappliedindisplays[1,2 ] .TheconventionalcommercialGd2 O3∶Eu3+ ismainlysynthesizedbyhightemperaturesolid statereactionandchemicalco precipitationmethods .Anadvancedperformanceofdisplaysrequireshighqualityphospho rssuchashighbrightnessandefficiency ,monodisper sityandfinegrainsize .Muchresearchhasanticipatedthatsubmicrometer sizedandnanometerluminescentmaterialswillhavethesepotentialadvantages[3～ 8] ,sosubmicrometer sizedan…