Zn空位缺陷长余辉发光材料Zn1-δAl2O4-δ的研究

Zn Vacancy Defects as Luminescence Centers for Long Persistent Phosphor Zn1-δAl2O4-δ and Investigation of Its Properties

采用高温固相法在还原气氛下制备蓝色长余辉发光材料Zn1-δAL2O4-δ,并通过适当减少Z11AI2O4中Zn的计量比在材料中制造作为发光中心的Zn空位缺陷。利用X射线粉末衍射(XRD)仪对样品物相进行表征,并利用Debye-Scherrer公式计算材料的颗粒大小为45 nm,所制备的材料颗粒细小。对材料进行激发发射光谱测试,主发射峰位于467 nm。热释发光(TL)光谱测试表明材料中存在两个能级陷阱深度大小较合适的缺陷,分别为0.767 eV和0.836 eV。缺Zn计量比配比及还原性气氛燔烧均能显著提髙材料缺陷浓度并改善材料的发光性能,所制备的发光材料目测余辉时间达4 h。对材料的发光机理进行了探讨。

Bluishlong persistent phosphor (LPP) Zn1-δAL2O4-δwas fabricated using a solid-state method in a reducing atmosphere. Zn vacancies, the luminescence centers in phosphors, were produced by decreasing a proper amount of Zn. Structural properties of the as-synthesized samples were characterized by X-ray powder diffiactometer (XRD). The particle size of the phosphors was 45 nm, which was calculated by the Debye-Scherrer formula. There was one main emission peak of the phosphors at 467 nm affirmed by photoluminescence (PL). The thermoluminescence (TL) showed that there were two defects in the material with proper trap depths, 0.767 eV and 0.836 eV respectively. Both Zn-deficient ratio and reducing atmosphere could significantly increase the material-defect concentration and improve the luminescence properties of the materials. The LPP materials were observed to have glowed to 4 hrs in darkroom. The photoluminescence mechanism of the Zn1-δAL2O4-δ materials was also discussed.