简介:四lanthanide协作建筑群,也就是[行(2,3-DClBA)3(5,5-dmebipy)(H2O)]2(Ln=Sm(1),Eu(2),Dy(3),惊讶(4));2,3-DClBA=2,3-dichlorobenzoate;5,5-dmebipy=5,5-dmethylbipyridine)被元素的分析,红外线的光谱学和单个水晶X光检查衍射综合并且描绘。调查结果显示建筑群3是一个dinuclear分子,并且中心Dy3+是八坐标的。每个dinuclear单位能被H债券和卤素卤素相互作用连接。建筑群2的光性质建议了Eu3+离子的典型强烈排出物。热分析证明建筑群在三分解了步:协作水然后第一被失去中立ligand5,5dmebipy被失去,最后,2,3-DClBAligand被失去。
简介:ThephaseandmorphologytransformationduringthehydrothermaltreatingprocessofY2O3wasevaluatedwithX-raydiffcrcnce(XRD),scanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM),particlesizeandspecificsurfaceareadetermination.TheresultsshowedthatthecubicY2O3didnottransferintohexagonalY(OH)3inpurewater.Therefore,purehexagonalY(OH)3withnanotubeandmicrorodmorphologieswereobtainedbyhydrothermaltreatingY2O3at150℃for12hin15mlof2mol/LNaOHsolutionwithandwith-outPVAorPEGItwassuggestedthatthecharacteristicpreferentialgrowthofY(OH)3wasattributedtothestructureanisotropyofhexahedronY(OH)3.TheadditionofPVAorPEGcouldpromotetheformingprocessofnanotubesbyselectiveadsorptionondifferentcrystalplanes,whichalteredthegrowthratealongdifferentdirectionsandresultedinthediffusionlimitofconstructingionsinthecentertopofrods.Finally,Y(OH)3:EuandY2O3:Eunanotubeswerealsosynthesizedbyusingthismethod,andtheirphotoluminescencepropertieswereevaluated.
简介:Thesolutionreactionmechanisms,composition,donoratoms,propertiesofcoordinatelinkandstabilityofthecomplexesonthesystemsofadrenalinewithNa3+,Gd3+andTm3+havebeenstudiedbypH-potentiometrictitrationandelectronicspectroscopy.Adrenalineperturbsthef-felectronictransitionofNd3+andTm3+sothattheabsorptionspectraoftheircomplexesareshiftedtowardlongerwavelengths.Theabsorptionspectraofthecomplexesformedbythethreef-blockelementionswithadrenalineareshiftedtowardshorterwavelengthswiththeincreaseofPHinΔγ=350~650nm
简介:YbAl3(BO3)4crystalofgoodopticalqualitywasgrownbythefluxmethod.ThestructureofYbAl3(BO3)4crystalwasdeterminedbysingle-crystalX-raydiffraction.TheexperimentshowsthatYbAl3(BO3)4belongstothedoubleborateswithatrigonalstructure.ThespacegroupisR32anditsunitcellconstantsweremeasuredtobea=0.92965nm,c=0.72129nm,V=0.53673nm3,Z=3.Thetransmittancespectraweremeasured.Thecut-offofYbAl3(BO3)4crystalis216nm,andtherearetwoabsorptionpeakslocatedat940and975nmfrom190nmto2600nm.ThethermalpropertiesofYbAl3(BO3)4crystalwerestudiedforthefirsttime.Theaveragethermalexpansioncoefficientsweredeterminedtobe2×10-6/℃,9.5×10-6/℃alonga-andc-direction.ThespecificheatofYbAl3(BO3)4crystalwasmeasuredtobe0.6695J·(g·℃)-1atroomtemperature.AllresultsindicatethattheYbAl3(BO3)4crystalisanexcellentstoichioimetriclasermaterial.
简介:Er3+-Tm3+-Yb3+tri-dopedBaMoO4phosphorsweresynthesizedbyco-precipitationtechniqueandcharacterizedbyX-raydiffractionanalysis,absorptionstudyandfieldemissionscanningelectronmicroscopyanalysis.Upconversionaswellasdownconversionluminescencestudieswereperformedbyusingnearinfrared(980nm)andultraviolet(380nm)excitations.Energyleveldiagram,pumppowerdependenceandcolourcoordinatestudywereutilizedtodescribethemulticolorupconversionemissionproperties.Undersingle980nmdiodelaserexcitationthedualmodesensingbehaviourisrealizedviaStarksublevelsandthermallycoupledenergylevelsoftheTm3+andEr3+ionsinthepreparedtri-dopedphosphors.AcomparativefluorescenceintensityratioanalysisforintegratedemissionintensitiesarisingfromtheStarksublevels{1G4(a)and1G4(b)}andthermallycoupledenergylevels{2H11/2and4S3/2}oftheTm3+andEr3+ions,respectivelywascarriedoutinthepreparedtri-dopedBaMoO4phosphors.ThemaximumsensitivityforthermallycoupledenergylevelsoftheEr3+andStarksublevelsoftheTm3+ionwasreported.Thedevelopedphosphorscouldbeusefulinthedisplaydevicesandopticalthermometricapplications.
简介:本文采用高温团相反应合成TCaTiO3∶Pr3+红色发光材料、报道了Pr3+激活的CaTiO3的光谱特征及长余辉特性,并与CaS∶Eu的光谱特性及长余辉进行了比较。CaTiO3∶Pr3+将是一种具有广泛用途的新材料
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.
简介:Calciumtitanatedopedwithpraseodymiumwaspreparedthroughsolidstatereactionanditexhibitedintenseredemissionat612nm.Phosphorswerecharacterizedforphotoluminescence,thermo-luminescenceandafterglowemissions.Studyofeffectsofrareearthsonphotoluminescenceaswellasafterglowintensitywasreported.Presenceofgadoliniumenhancedluminescence.Presenceofsomemonovalentionsenhancedbothafterglowandphotoluminescenceemission.Thermo-luminescenceglowcurveswereanalyzedand...
简介:Er~(3+)andLa~(3+)codopedY_2O_3nanocrystallinepowdersweresynthesizedbygelcombustionmethodandcharacterizedwiththermalanalysis,X-raydiffraction(XRD),transmissionelectronmicroscopy(TEM),high-resolutionTEM(HRTEM)techniquesandfluorescencespectroscopy.Afterbeingcalcinedat1200oC,the(Y_(1–x)La_x)_2O_3:Er~(3+)powderswereconfirmedtobecubicY_2O_3phasewiththecrystallinegrainsizeintherangeof20–40nm.TheEr~(3+)emissionat1.53μmfromthe~4I_(13/2)→~4I_(15/2)transitionwasobserved,whichwasfoundtobeenhancedbyintroducingLa~(3+)ions.SuchenhancementcouldbeattributedtotheadjustmentofEr~(3+)ions'localenvironmentbythecodopingofLa~(3+)ions,leadingtotheincreasedgroundstateabsorptioncrosssectionofEr~(3+)ions.
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简介:Duetotheremarkablemagnetoresistance(MR)effectonperovskite-typemanganite,magnetoelectronicsandspintronicshavebecomeattractivesubjectsofexperimentalandtheoreticalinvestigationsfortheapplicationpurpose.(La0.9Nd0.1)2/3Ca1/3Mn1-xFexO3(x=0,x=0.05)werepreparedsuccessfullybysol-gelmethod.Thestructure,magneticproperties,andtransportpropertiesofthecompoundswereinvestigated.Themagnetoresistanceeffectdependsonthecompositionandthetemperature.XRDpatternsshowthatthecompoundisasinglephasepolycrystalwithpseudocubicstructure.Alargenegativeisotropicmagnetoresistanceeffectinthesampleswereobservedatlowtemperatureregion.ThemaximumMRofthesampleswas77%and97%,respectively.Itwasmostlikelyduetothescatteringorthetunnelingtransportofspin-polarizedcarriersinlatticeunderstrongmagneticfield.
简介:InordertosensitizetheluminescenceofEu3+ionsinheavymetalglass,zincleadborateglasssamplescontainingvariousconcentrationsofEu3+andTb3+ionswerepreparedtostudytheTb3+toEu3+non-radiativeenergytransferphenomena.EnergylevelstructuresofTb3+andEu3+ionswereplottedtoshowtheexcitationandenergytransferroutes.EfficientenergytransferfromTb3+toEu3+wasobservedandstudiedqualitativelyintermsofdopingconcentrations.Thesensitizationturnedouttobelesseffectivethanexpected.FurtherstudiestocharacterizetheoxidationofTb3+intotetravalentstateandtoexaminethemechanismofenergytransferareproposed.
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简介:Eu3+/Sm3+codopedBiPO4黄磷与没有表面活化剂的环境经由一个灵巧的热水的方法被综合。X光检查衍射分析证明样品拥有了标准BiPO4单斜晶的结构。扫描电子显微镜学图象证明所有样品与像梭的形状分散得好的、测微计大小的晶体创作了。到Eu3+的从Sm3+的精力转移被光系列和Sm3+4G5/26H5/2排放的腐烂过程证实。橘子红光能在Eu3+/Sm3+codopedBiPO4黄磷被获得。Sm3+4G5/26H5/2排放的平均一生在BiPO4:0.03Sm3+在BiPO4:0.03Sm3+从2.70ms减少了到2.37ms,0.05Eu3+。在395nm附近的强壮、宽的吸收乐队,从Eu3+的7F05L6转变和Sm3+的6H5/24K11/2转变发源,资助BiPO4:Eu3+,有近紫外激动的white-light-emitting二极管的域里的潜在的应用程序的Sm3+黄磷。
简介:Cr的Nanopowder:Cr的GGG和nanopowder,Nd:有从0.1at.%到1.5at.%的Cr3+的不同集中的GGG被大音阶的第五音胶化方法用醋酸和乙烯乙二醇综合。热gravimetric分析和微分扫描热量测定(TGA-DSC),X光检查衍射(XRD)和光致发光光谱学被用来描绘粉末。当在1000点对待时,雏晶尺寸是大约58nm?????????????????猯灵?匠?猼'T资???猼灵?????????猯'T??猼灵???? ̄?????猯'T????猯灵??猼'T?????吗????????????????‵渠????????浮??
简介:LanthanidedopedNaYF4microcrystalsweresynthesizedviaafacilehydrothermalmethod.MulticolorupconversionluminescencewasobservedinNaYF4microcrystalsdopedwithYb3+/Er3+,Yb3+/Tm3+,andYb3+/Er3+/Tm3+undertheexcitationof980nminfraredlight.Importantly,theexcitationpowerdensitydependenceofupconversionemissionintensityindicatedclearlytheenergytransferfromTm3+toEr3+ionsundertheexcitationoflowpowerdensity(5×102–9×102W/cm2).Meanwhile,theinverseenergytransferfromEr3+toTm3+ionsundertheexcitationofrelativelyhigherpowerdensity(4.1×104–4.9×104W/cm2)wasalsorevealed.ThiswasadirectevidenceforreversibleenergytransferbetweenEr3+andTm3+ions.Undertheexcitationofhighpowerdensity(4.1×104–4.9×104W/cm2),darksensitizerswerealsomotivatedsothatthebottleneckeffectofhighconcentrationYb3+iondopingwasbroken.ThiswasthemainreasonforrealizinghighupconversionefficiencyofthesampleswithheavydopingofYb3+ion.