已有 1531 次阅读 2024-1-11 22:13 |系统分类:论文交流

论文题目:Unraveling electron liberation from Bi2+ for designing Bi3+-based afterglow phosphor for 

anti-counterfeiting and flexible X-ray imaging


全文下载:Lyu 6.pdf


(1). VRBEs in the Bi2+ 2P1/2 ground state in NaYGeO4 and NaLuGeO4 were experimentally determined 

by thermoluminescence study.

(2). Electron liberation from Bi2+ has been evidenced.

(3). Fully control of Bi3+ trapping depth via conduction band engineering.

(4). Rational design of new Bi3+-based afterglow phosphor.


It is challenging to rational design persistent luminescence and storage phosphors with high storage capacity of electrons and holes after X-ray charging. Such phosphors have potential applications in anti-counterfeiting and X-ray imaging. Here we have combined vacuum referred binding energy diagram (VRBE) construction, photoluminescence spectroscopy, and thermoluminescence to study the trapping processes of charge carriers in NaYGeO4. In NaYGeO4:0.004Bi3+ and NaYGeO4:0.004Bi3+,0.005Ln3+ (Ln = Tb or Pr), Bi3+ appears to act as a shallow electron trap, while Bi3+ and Ln3+ act as deep hole trapping and recombination centres. We will show how to experimentally determine the VRBE in the Bi2+ 2P1/2 ground state in NaYGeO4 and NaLuGeO4 by thermoluminescence study. The electron trap depth produced by Bi3+ codopant in NaLu1-xYxGeO4:0.003Bi3+,0.008 Tb3+ can be adjusted, by increasing x, resulting in conduction band engineering. By combining Bi3+ as an electron trap and Bi3+ and Tb3+ as the hole traps, excellent X-ray charged afterglow phosphors were developed. The integrated TL intensity of the optimized NaYGeO4:0.004Bi3+ and NaYGeO4:0.003Bi3+,0.008Tb3+ after exposure to X-rays is about 4.5 and 1.1 times higher than that of the state-of-the-art BaFBr(I):Eu2+ storage phosphor. Intense initial Tb3+ 4f → 4f afterglow appears in NaYGeO4:0.003Bi3+,0.008Tb3+ and more than 40 h afterglow is measurable in NaYGeO4:0.004Bi3+ and NaYGeO4:0.003Bi3+, 0.008 Tb3+ after X-ray charging. We will show proof-of-concept anti-counterfeiting and X-ray imaging applications by using the developed afterglow phosphors and CsPbI3 quantum dots. This work not only provides experimental evidence on the VRBE in the Bi2+ 2P1/2 ground state in NaYGeO4, but also shows how to design and develop good afterglow phosphors for anti-counterfeiting and X-ray imaging by deeply studying and controlling the trapping processes of charge carriers in bismuth and/or lanthanides doped inorganic compounds.


上一篇:设计LiTaO3:Ln3+,Eu3+ (Ln = Tb or Pr)光存储材料及其在防伪和柔性X射线成像应用
收藏 IP: 218.107.223.*| 热度|


该博文允许注册用户评论 请点击登录 评论 (0 个评论)


Archiver|手机版|科学网 ( 京ICP备07017567号-12 )

GMT+8, 2024-4-15 17:24

Powered by

Copyright © 2007- 中国科学报社