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The upconversion (UC) luminescence and color tunable properties of Tb3+ ions were investigated by steady spectral under 980 LD excitation in the Ca0.15Zr0.85O1.85:Yb,Tb inverse opals fabricated by the self-assembly technique in combination with a sol-gel method. The in-hibition of UC emission was inspected if the Tb3+ UC emission band was in the regions of the photonic bandgap, while enhancement of the UC emission occurred if the UC emission band located at the edge of the bandgap. Color modification of the UC emission was successfully ob-tained by the suppression or enhancement effect of the photonic band gap on the UC emission. 相似文献
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The effect of glass network modifier R2O (R=Li, Na, K) on upconversion luminescence in Er3+/Yb3+ co-doped NaYF4 oxyfluoride glass-ceramics was investigated. NaYF4 nanocrystals with different sizes were... 相似文献
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用高温固相法在空气中制备了Bi掺杂碱土金属氟磷酸盐[(M5(PO4)3F,M=Ca,Sr,Ba)]荧光粉,通过X射线衍射和荧光光谱对其晶体结构和紫外–可见发光性质进行了分析。结果表明:观察所有样品都得到Bi3+位于紫外波段的特征发光,观察Ca5(PO4)3F:Bi和Sr5(PO4)3F:Bi样品可同时到源于Bi2+明亮的黄白色宽带发射。根据光谱结果和结构特性,分析Bi在氟磷酸盐中的多价态特性及形成机理,结果显示:在氟磷酸盐中存在2种Bi3+发光中心,分别占据2种不同的阳离子(M2+)格位;在Ca5(PO4)3F:Bi和Sr5(PO4)3F:Bi中,位于M2+(1)位点的Bi3+可被电荷补偿等因素的非常规还原作用还原为Bi2+,Bi掺杂的Ca5(PO4)3F和Sr5(PO4)3F有望成为一类新型的黄白色荧光粉。 相似文献
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本工作研究了卤素离子含量对卤磷酸钙固溶体中Bi离子的价态和发光性能的影响。荧光分析表明, 卤素磷酸钙中的Bi2+/Bi3+可以通过其F-/Cl-组分变化实现有效调控; 当卤素离子全部为Cl-离子时, 晶体中Bi2+全部消失。上述现象的主要原因在于, 当卤素离子为F或者Cl时, 晶体中与其邻近的Ca(2)位点可以被分裂为Ca(2)a 或Ca(2)b两种不同的格位, 而Ca(2)a位点则有利于实现Bi3+的自还原。上述研究结果可以为Bi离子在晶体中的价态调控提供指导。 相似文献
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白雪 杨钊烁 徐赞 寸阳珂 字映竹 赵和平 宋友艳 何彦妮 Asif Ali Haider 邱建备 宋志国 黄安君 Cherkasova Tatiana 杨正文 《SCIENCE CHINA Materials》2023,(6):2408-2417
光致变色和光致发光是两种有趣的光学现象,它们在单一材料中的结合可以应用于多级防伪和光学记忆存储等器件.然而,在双光刺激下开发一种同时具有光致变色和光致发光的材料是一个挑战.本工作利用缺陷诱导色心的形成制备了光致变色SrWO4:Yb3+,Er3+,Bi3+荧光粉,在254 nm紫外光和473 nm激光交替照射下,获得了从白色到暗黄色的可逆光致变色.SrWO4:Yb3+,Er3+,Bi3+的光致变色效应引起了可逆光致发光调控.基于相应的颜色对比和发光强度变化,实现了SrWO4:Yb3+,Er3+,Bi3+荧光粉的光存储和防伪应用.在实际应用中,柔性SrWO4:Yb3+,Er3+,Bi3+薄膜作为一种很有前途的替代材料,既能满足多样化的要求又能提... 相似文献
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A series of K3Gd(PO4)2:Tb3+,Sm3+ phosphors were synthesized through solid state reaction. By co-doping Tb3+ and Sm3+into K3Gd(PO4)2 host and singly varying the doping concentration of Sm3+, tunable colors from green to yellow and then to orange were obtained in K3Gd(PO4)2:Tb3+,Sm3+ phosphors under the excitation at 373 nm. The energy transfer process from Tb3+ to Sm3+ was verified through luminescence spectra and fluorescence decay curves. Moreover, the energy transfer mechanism was demonstrated to be the quadrupole-quadrupole interaction. The results indicated that K3Gd(PO4)2:Tb3+,Sm3+ phosphors could be a potential application for n-UV white light emitting diodes. 相似文献