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物理化学学报 2013
钙钛矿结构荧光材料mzro3:eu3+,a(m=ca2+,ba2+;a=li+,na+,k+)?的制备及其发光性质Keywords: cazro3:eu3+,aandbazro3:eu3+,a(a=li+,na+,k+),chargecompensator,combustionsynthesis,photoluminescence Abstract: calciumandbariumzirconatepowdersbaseduponcazro3:eu3+,aandbazro3:eu3+,a(a=li+,na+,k+)werepreparedbycombustionsynthesismethodandheatingto~1000℃toimprovecrystallinity.thestructureandmorphologyofmaterialswereexaminedbyx-raydiffraction(xrd)andscanningelectronmicroscopy(sem).xrdresultsshowedthatcazro3:eu3+,aandbazro3:eu3+,a(a=li+,na+,k+)perovskitespossessedorthorhombicandcubicstructures,respectively.themorphologiesofallpowderswereverysimilarconsistingofsmall,coagulated,cubicalparticleswithnarrowsizedistributionsandsmoothandregularsurfaces.thecharacteristicluminescencesofeu3+ionsincazro3:eu3+,a(a=li+,na+,k+)latticeswerepresentwithstrongemissionsat614and625nmfor5d0→7f2transitionswithotherweakeremissionsobservedat575,592,655,and701nmcorrespondingto5d0→7fntransitions(wheren=0,1,3,4respectively).inbazro3:eu3+boththe5d0→7f1and5d0→7f2transitionsat595and613nmwerestrong.photoluminescenceintensitiesofcazro3:eu3+sampleswerehigherthanthoseofbazro3:eu3+lattices.thisremarkableincreaseofphotoluminescenceintensity(correspondingto5d0→7fntransitions)wasobservedincazro3:eu3+andbazro3:eu3+ifco-dopedwithli+ions.anadditionalbroadbandcomposedofmanypeaksbetween440to575nmwasobservedinbazro3:eu3+,,asamples.theintensityofthisbandwasgreatestinli+co-dopedsamplesandlowestfork+dopedsamples.
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