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51 个结果
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  • 简介:做Eu2+的第三的氮化物黄磷,Sr2Si5N8:Eu2+,用高温度被综合固态方法。X光检查衍射(XRD)模式证明那个Sr2Si5N8单个阶段被获得。因为Eu2+的半径比Sr2+的小,格子参数缩小了。排放系列给一个宽广排放乐队看了。随Eu2+集中的增加,排放山峰位置是redshifted。刺激系列给从主人和Eu2+离子的4f74f65d1转变发源的二个刺激乐队看了。与Sr2Si5N8的光特征相比:Eu2+和CaS:Eu2+黄磷在不同温度,二黄磷的紧张随温度的增加逐渐地减少了,这被注意。Sr2Si5N8的紧张:Eu2+黄磷比CaS的强壮:Eu2+,它显示前者的光特征比后者的好。

  • 标签: 发光性 稀土 碱性金属 氧化氮
  • 简介:Trivalentdysprosium(Dy3+)activatednanocrystallineyttriumvanadate(YVO4)phosphorwassynthesizedviaco-precipitationmethod.ThepreparedsampleswerecharacterizedbyX-raydiffraction(XRD),Fouriertransforminfraredspectroscopy(FTIR),scanningelectronmicroscopy(SEM),opticalabsorptionandphotoluminescence(PL)techniques.TheXRDpatternsrevealthetetragonalcrystallinephase.SEMimagesrevealthatDydopedYVO4nanocrystalsareagglomerated.EDAXconfirmstheformationofYVO4:Dy.FTIRspectrumshowstwostrongabsorptionbandsat459and761cm-1.Opticalabsorptionspectrumshowedthesurfacedefectsintheas-preparedsamples.ThePLemissionspectrumshowstwocharacteristicemissionbandsat485and575nm.Thestrongyellowemissionpeakat575nmisassignedto4F9/2→6H13/2hypersensitivetransitionofDy3+ions,StudyofCIEchromaticitydiagramindicatesthesuitabilityofthephosphorforthedevelopmentofyellow-greenLEDs.

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  • 简介:Theblue-greenemittingEu2+andNd3+dopedpolycrystallinebariumaluminate(BaAl2O4:Eu2+,Nd3+)phosphor,waspreparedbyasolution-combustionmethodat500oCwithoutapost-annealingprocess.Thecharacteristicvariationinthestructuralandluminescencepropertiesoftheas-preparedsampleswasevaluatedwithregardstoachangeintheBa/Almolarratiofrom0.1:1to1.4:1.Themorphologiesandthephasestructuresoftheproductswerecharacterizedbyscanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),X-raydiffraction(XRD)andX-rayphotoelectronspectroscopy(XPS),whiletheopticalpropertieswereinvestigatedusingultra-violet(UV)andphotoluminescence(PL)spectroscopy,respectively.TheXRDandTEMresultsrevealedthattheaveragecrystallitesizeoftheBaAl2O4:Eu2+,Nd3+phosphorwasabout70nm.Thebroad-bandUV-excitedluminescenceofthephosphorswasobservedatλmax=500nmduetotransitionsfromthe4f65d1tothe4f7configurationoftheEu2+ion.ThePLresultsindicatedthatthemainpeaksintheemissionandexcitationspectrumofphosphorparticlesslightlyshiftedtotheshortwavelengthduetothechangesinthecrystalfieldduetothestructurechangescausedbythevariationinthequantityoftheBaionsinthehostlattice.

  • 标签: 发光性能 铝酸钡 燃烧合成 荧光粉 X射线光电子能谱 扫描电子显微镜
  • 简介:TakingthetransportoftotalphosphorpollutantsintheBeijingMiyunreservoirforexample,wehaveobtainedthreedimensionaldistributingregularityoftotalphosphorpollutantsbythecalculationofthelinearinterpolationvalueofeachpointbetweenhorizontallayers.Thecredibilityanalysisinallusiontothismethodwascarriedoutandtheprogrammingschemeforrealizingthismethodwassetforth.

  • 标签: 水域 荧光体 三维数学模型 蓄水池
  • 简介:(Ba0.66Sr0.33)Mg0.8Al11.47O19:Tm0.013+(BSMA:Tm3+)phosphorwassynthesizedbysolid-statereactions.ThesamplewascharacterizedbyX-raydiffraction(XRD),scanningelectronicmicroscope(SEM),vacuumultraviolet(VUV)spectra,ultraviolet(UV)spectraandFT-IRspectrum.XRDpatternrevealsthatBSMA:Tm3+hasthesamestructureasBaAl12O19phase.SEMimageillustratesthatthephosphorhasthehexagonalshapeanddeepslicestructure.VUVandUVemissionspectraat20,50and100Kshowthatthelowtemperatureluminescenceintensitiesbecomeweakgraduallywiththeincreasingofthetemperatureunder147and254nmexcitation.Thestrongbroadbandpeaksataround357and397nmandthepeakat516nmunder147nmexcitationallcorrespondtothecharacteristictransitionsofTm3+ions.However,underUV(254nm)excitation,themainpeakbecomes530nmwhichhasveryhighlineintensity,andthepeaksatabout362and403nmareveryweak.Theexcitationspectrumat20Kshowsthattherearethreeabsorptionpeaksataround153,186and193nmwhen516nmemissionismonitored.Theabsorptionpeaksof[AlO4],[AlO6]andAl-OcanbeobservedinFT-IRspectrum.

  • 标签: VACUUM ULTRAVIOLET low temperature LUMINESCENCE Tm3+
  • 简介:SphericalYAG:Ce3+phosphorparticleswithnarrowsizedistributionwerepreparedbyspraypyrolysis.Theeffectsoftheconcentrationofsolution,theflowrateofcarriergasandtheannealingtemperatureonthephosphormorphologywerestudied.Theproductivityofprecursorparticlesshowsatrendofdropafterrisingwiththeincreaseofconcentration.Raisingtheflowrateofnitrogencanimprovetheproductivityoftheprecursorparticles.Phosphorpreparedbyspraypyrolysishasobviouslyhigheremissionintensitythanthatsynthesizedbysolidstatereaction,spraypyrolysismakesCe3+ionswelldistributedinthecrystallatticeastheluminescentcenters,andphosphorparticleshaveregularsphericityandnarrowsizedistribution.

  • 标签: 钇铝石榴石 稀土 热解 制备 发光二极管 荧光性质
  • 简介:Differentfluxeswereusedtosynthesizelongpersistencephosphors,calciumsulfidesactivatedbyEu2+andTm3+,byconvenientsolid-statemethod.ThephosphorusingNH4Fasafluxhasgoodcrystallinityandlargeparticlesize,itsstabilityagainstwaterandotheratmosphericcomponentsisenhanced,anditsafterglowislongerandfluorescentintensityismoreintensethanthoseofthephosphorusingNH4Clasflux.TheirPLintensitiesvariedwithtimeinmoistairweremeasured,noremarkablechangewasfoundforthosepreparedwithNH4FfluxincontrastwithNH4Clasflux.SousingNH4Fasfluxisagoodmethodtoenhancethestabilityofalkalineearthsulfides.

  • 标签: 磷光体 CaS:Eu^2+/Tm^3+ 化学稳定性 稀土 硫化钙 铕二价
  • 简介:Heterogeneousprecipitationmethodwasusedtopreparedsurfacecoatingonself-madeBaMgAl10O17:Euphosphor.Resultsillustratethatthecoatingfilmcanbesilicondioxideinamorphousstatewith50nminthickness.Photoluminescenceresultsindicatethatthecoatinglayerpresentsanobservableimprovedeffectontheenhancementofthermalstability.Whenbakedat600℃for1h,theluminanceofcoatedBAMkeepsat92%higherthanthatofuncoatedBAMby23%.ThisprotectiveeffectcanbeattributedtothehighcompactdegreeanduniformityofthisamorphousSiO2coatingfilmwhichisservedasadiffusionblocklayertoinbreakoxygenatom,thusreleasestheoxidationextentofEu2+effectively.

  • 标签: PDP BaMgAl10O17∶Eu THERMAL DEGRADATION THERMAL stability
  • 简介:Eu3+activatedSr1–xEuxZrO3(x=0.01–0.04)phosphorwithperovskitestructurewassuccessfullysynthesizedbyusingcombustionmethod.Thestructure,morphologyandopticalpropertiesofthematerialwerecharacterizedbyX-raydiffraction,scanningelectronmicroscopyandfluorescencespectrometry.TheXRDresultsindicatedthatcrystalsofSrZrO3:Eu3+belongstotetragonalperovskitesystem.ThephosphorcouldbeeffectivelyexcitedbyUVlightandtheemissionspectraresultsindicatedthatreddish-orangeluminescenceofSrZrO3:Eu3+duetomagneticdipoletransition5D0→7F1at593nmwasdominant.Thus,thepreparedphosphorshowedremarkableluminescentpropertieswhichfindapplicationsinfieldemissiondisplay(FED)andplasmadisplaypanel(PDP)devices.

  • 标签: 钙钛矿结构 铕激活 荧光粉 光学特性 合成 扫描电子显微镜
  • 简介:现在的工作集中于微观结构和免费切的黄磷的机械性质上的空气晒黑的退火的影响合金。合金退火在象空气,真空和氮那样的三种退火的空气被进行。在退火以后,在recystallized谷物尺寸和铅粒子尺寸的可辨别的差别没与不同退火的空气被显得。合金的张力的力量在空中退火了或氮空气比那些的在真空空气退火高。在真空空气在合金的情况中退火了,机械力量被锌的蒸发减少。在在氮并且在空气空气退火的情况中,铅出汗被发生。然而,铅的反的分离被氧化铜层在表面上压制在空中退火了。这氧化铜层在制造过程期间导致收益的减少。因此,在氮空气合金退火以机械力量和收益是有利的。

  • 标签: 退火工艺 机械性能 切割技术 铜合金
  • 简介:Calciumtitanatedopedwithpraseodymiumwaspreparedthroughsolidstatereactionanditexhibitedintenseredemissionat612nm.Phosphorswerecharacterizedforphotoluminescence,thermo-luminescenceandafterglowemissions.Studyofeffectsofrareearthsonphotoluminescenceaswellasafterglowintensitywasreported.Presenceofgadoliniumenhancedluminescence.Presenceofsomemonovalentionsenhancedbothafterglowandphotoluminescenceemission.Thermo-luminescenceglowcurveswereanalyzedand...

  • 标签: perovskites 钙 titanates 红晚霞 稀土元素
  • 简介:Trivalentsamariumdopedbariummolybdate(BaMoO_4:Sm~(3+))redphosphorwassuccessfullysynthesizedbyhydrothermalmethod.Thecrystalstructure,morphologyandphotoluminescentpropertywerecharacterizedbyX-raydiffraction,fieldenvironmentalscanningelectronmicroscopyandphotoluminescencespectroscopy.TheresultsindicatedthatthesynthesizedBaMoO_4:Sm~(3+)phosphorconsistedofapurephasewithanoctahedralstructure.Themainexcitationpeakswerelocatedat362,404,445and477nm,respectively,andwereobviouslyobserved.Themainemissionpeakswerelocatedat533,566,602and646nm,respectively.Thephosphorsexhibitedaredperformanceat646nm,whichwasappropriatefortheultraviolet-lightemittingdiode(UV-LED)andblueLED.TheluminescentintensityofBaMoO_4:Sm~(3+)increasedwithanincreaseinthedopingamountofSm~(3+).Theluminescentintensityhadtheoptimalvalueforx=0.03.WhenthedopingamountofSm~(3+)wasfurtherincreased,theconcentrationquenchingphenomenonwasobserved.Monovalentlithium(Li+)cationwasusedasachargecompensator.TheluminescenceintensityfirstincreasedwithincreasingLi+dopingconcentration,andthendecreased.TheoptimalcontentofLi+wasabout2%.TheBaMoO_4:Sm~(3+)phosphorpreparedinthisstudycouldactassuperiorredphosphorforwhiteLEDs.

  • 标签: LUMINESCENT PHOSPHOR doping hydrothermal ultraviolet luminescence
  • 简介:Eu-activatedCaMoO4phosphorswereco-precipitatedinanaqueoussolution,andNH3·H2O,NH4HCO3and(NH2)2COaspre-cipitatingaidagentswerecomparedbasedonthemorphologyandparticlesizedistributionofthephosphorsamples.Sm3+assensitizerionwasinvestigatedontheluminescenceofCaMoO4:Eu,anditcouldstrengthenthe406nmabsorptionofthisphosphor.Atlast,thescheeliteCaMoO4:EuandwolframiteZnMoO4:Euwereselectedtocomparetheirhostabsorption.TheresultshowedthatthescheelitemolybdatehostexhibitedstrongerUVabsorptionthanwolframiteone.

  • 标签: CaMoO4 ZnMoO4 EUROPIUM SAMARIUM red PHOSPHOR
  • 简介:Whitebody-color(Y,Gd)BxV1-xO4-x:Eu3+phosphorswerepreparedbycoprecipitationreaction.UnderVUVexcitationat147nm,theredemissioncolorimetricpurityof(Y,Gd)BxV1-xO4-x:Eu3+phosphorismuchbetterthanthatofcommercialPDP(plasmadisplaypanels)phosphor(Y,Gd)BO3:Eu3+.Butitsrelativeemissionintensityisonlyabout90%ofthecommercialphosphor.

  • 标签: 共沉淀 平板电视 荧光材料 发光性能 稀土 掺杂
  • 简介:TheCa_2SiO_4:Dy~(3+)phosphorwassynthesizedbythehightemperaturesolid-statereactionmethodinair.TheemissionspectrumofCa_2SiO_4:Dy~(3+)phosphorshowsseveralbandsat486,575,and665nmunderthe365-nmexcitation.TheeffectsofLi~+,Na~+,andK~+ontheemissionspectrumofCa_2SiO_4:Dy~(3+)phosphorwerestudied,TheresultsshowthattheemissionspectrumintensityisgreatlyinfluencedbyLi~+,Na~+,andK~+.Thechargecompensationconcentrationcorrespondingtothemaximumemissionintensityisdifferentwithdifferentchargecompensations.

  • 标签: 光谱 光反射 硫酸钙 无机发光材料