CeO_2:Eu^(3+)纳米晶的发光特性与Gd^(3+)离子掺杂影响研究

Luminescence properties and doping effect of Gd^(3+) on CeO_2:Eu^(3+) nanocrystals

以尿素为燃烧剂,采用低温燃烧法制备了Eu3+单掺杂和Eu3+、Gd3+共掺杂CeO2纳米晶粉末,用X射线衍射(XRD)和透射电镜(TEM)对样品进行了结构分析和形貌表征。对掺杂Gd3+离子的CeO2:1%Eu3+纳米晶的光谱研究发现,随着Gd3+离子掺杂浓度的增加,5 D0→7F2跃迁与5 D0→7F1跃迁的强度比随之增加,这表明Eu3+离子的格位对称性有所下降,且有利于提高红橙光的比例。鉴于CeO2基质在300～390nm有强吸收,Eu3+掺杂CeO2纳米晶在近紫外激发LED荧光粉方面有潜在应用前景。

CeO2：1%Eu^3＋ nanocrystals were prepared by combustion method. By using Xray diffraction （XRD）,transmission electron microscope （TEM） and fluorescence spectrometer, the structural, morphological and luminescence properties of CeO2：1%Eu^3＋ nanocrystals were investigated. The results showed that under 365nm excitation the main e-mission peak of CeO2：1%Eu^3＋ nanocrystals were at 590. 5nm, which were attributed to5Do→7F1 of Eu^3＋. Under 465nmexcitation,the main emission were at 610nm and 631nm, originating from5Do→7F2 of Eu^3＋. The energy from CeO2 hostwas mainly transferred to Eua＋ ions at high-symmetry site was thinked. For Gda＋ doped CeO2：1%Eu^3＋ nanocrystals, theratio of5 D07→F2 toSD0→7 F1 emission intensity was increased with the increase of Gd^3＋ ion concentration, this result indica ted that the symmetry of Eua＋ ion was decreased.