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：Y3Al5O12:Ce3+isthemostfamousphosphormaterialduetoitsexcellentphotolumincentproperties.Here,throughfirst-principlescalculation,theeffectofcarboninterstitialdefectsonY3Al5O12:Ce3+phosphorwasinvestigated.Itisfoundthatthecarboninterstitialstendtooccupythenext-nearestsitesofCe3+ioninY3Al5O12:Ce3+lattice.Specially,theseinterstitialdefectscanshortentheCe3+-O2-bondlength,leadingtoalargercrystalfieldsplittingof5dorbitaloftheCe3+atomandbigger5dcentroidshift.ThesetwofactorscausetheemissionspectrumofY3Al5O12（C）:Ce3+redshiftcomparedwiththatofY3Al5O12:Ce3+.Moreover,withourcomparisonexperiment,wefindthattheY3Al5O12（C）:Ce3+hasanobviousredshiftcomparedwiththatofY3Al5O12:Ce3+system,whichisinaccordwithourfirstprinciplescalculation.OurworksystematicallyinvestigatestheimpactofthecarboninterstitialdefectonY3Al5O12:Ce3+,andprovidesanewroutetotunetheemissionspectruminY3Al5O12:Ce3+.

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简介：AseriesofCeB6-dopedandCeO2-dopedCa1-xSiAlN3:xCe3+（denotedasCASN:Ce3+@CeB6andCASN:Ce3+@CeO2,respectively）weresynthesizedbyalloy-nitridationmethodunderhigh-puritynitrogenatmosphere.Themorphologies,crystalphases,andluminescencepropertieswereinvestigatedindetail.WithanincreaseintheconcentrationofCeB6,theunitcellvolumeofCASN:Ce3+@CeB6slightlyincreasesduetothesubstitutionbetweenions,whichleadstoachangeofmicrostructurearoundCe3+.CASN:Ce3+@CeB6efficientlyemitsyellow-orangelightwithamaximumemissionintensityataround550nmforthecontentxof0.01（beingincomparablesituation,CASN:Ce3+@CeO2isx=0.04）whenexcitedat460nm.ComparedwithCASN:Ce3+@CeO2,theredemissioncomponentofCe3+inCASN:Ce3+@CeB6ismuchstronger.Thisisascribedtoenergytransferofintra-Ce3+（withinoneCe3+ion）andinter-Ce3+（betweenCe3+andCe3+ions）.Inaddition,thereplacementsofN3-（0.132nmforCN=4）andO2-（0.124nmforCN=4）byB2-（0.140nmforCN=4）,whichcanleadtoamarkedexpansionofthehostlatticeandadecreaseoftheoxidationofsamples,arealsoresponsiblefortheincreaseofredemissioncomponent.Furthermore,CASN:Ce3+@CeB6phosphorhasanexcellentthermalstabilitybecauseofthepartialsubstitutionofCe-O（Ce-N）bondsbymorecovalentCe-B.Asaresult,theoutstandingluminescentpropertiesofCASN:Ce3+@CeB6phosphormakeitpracticaltouseinthesinglephosphor-coatedhigh-color-renderingpowerwhiteLED.

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