惰性壳层介电效应对核壳结构上转换纳米晶发光性能的影响

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关键词：核壳结构纳米晶；上转换发光；惰性壳层；介电常数中图分类号：0482.31 文献标识码：ADOI：10.37188/CJL.20250102 CSTR：32170.14.CJL.20250102

Influenceof Inert ShellDielectric Effecton Luminescent Properties of Core-shell Upconversion Nanocrystals

WANG Jin'，YU Shijie1，HU Yanqing²，SHAO Qiyue1* （1.SchoolofMaterials Scienceand Engineering，Southeast University，Nanjing211189，China; 2.SchoolofMaterialsScienceandEngineeing，Suzhou UniversityofcienceandTechnology，Suzhou25o9，China） *CorrespondingAuthor，E-mail：qiyueshao@seu.edu.cn

Abstract：A series of core/shell upconversion nanocrystals（UCNCs） featuring β-NaYF4：Yb/A3+（ A =Er，Ho，Tm）cores and distinct inert shells（ NaLuF4 ，NaYF4，NaGdH 4 ）were synthesized through the co-precipitation method combined with a successive layer-by-layerstrategy.Theinfluenceofshellcompositiononluminescentpropertieswasinvestigatedandtheunderlying mechanism was analyzed through upconversion emision spectrumand luminescentlifetime measurements.Experimental resultsindicatethatboththeupconversionluminescenceintensityandtheYbluminescent lifetieofcore/shell UCNCs depends on the composition of inert shell，exhibiting a gradual decrease in the order of NaLuF 4> NaYF 4> NaGdF 4 This trendsuggestsprogressvelyducedcapabilitisofthreekindsofinertshellinsuppressngsurfacequenching.Theinfluences of three kindsof inertshellbecome more pronouncedinaqueous environmentswithhighquenching probabilities.Theoreticalcalculationsreveal thatthevariationindielectricconstantamongtheinertshellmaterialsmayplayacriticalrole，with NaLuF showing thelowestrelative dielectric constant.The shellayer with lowdielectricconstantcan mitigate theelectric dipole interaction between Yb3+ ions in the core and surface-adsorbed ligands，thereby suppressing non-radiative energy losses. This studyrevealstheposibleregulatorymechanismof thedielectricefectof inertshellonthesurfacequenchingeffect，providing valuable guidance for the compositional design of high-brightness core/shell UCNCs.

KeyWords：core-shellnanocrystal；upconversion luminescence；inert shell；dielectric constant

1引言

稀土离子掺杂的上转换纳米晶具有吸收多个低能量光子后发射高能量光子的特性。（剩余15273字）