摘要
随基质材料的不同,Bi^(3+)离子可以产生深紫外、可见乃至近红外区域的发光,经常被用作各类发光材料中的激活离子。对Bi^(3+)掺杂的能级结构和发光机理研究有助于新型发光材料的设计和性能改进。本文对近期开展的第一性原理计算的相关方法和结果进行分析总结,讨论了Bi^(3+)掺杂体系基态和激发态的局域结构和电子结构共性,借助位形坐标图分析讨论了该类材料激发、弛豫以及发射的动力学过程。所研究的激发态主要涵盖了Bi^(3+)的6s16p1电子组态、配体⁃掺杂离子电荷迁移态6s26p1加束缚空穴、金属⁃金属电荷迁移态6s1加束缚电子以及电子在离子对间迁移形成的Bi^(2+)⁃Bi^(4+)离子对等4种类型。全文力图从Bi^(3+)光谱学特征的实验指认出发,通过总结各种发光过程的物理图像及理论描述,以若干代表性例子作为依托,展示有关理论和计算对实验现象的分析和指引作用。同时,也简要讨论了发光中心局域结构、基质带隙、缺陷能级等与Bi^(3+)离子发光性质之间的联系。
The trivalent bismuth ions can produce,depending on the host,luminescence in deep ul⁃traviolet,visible and even near-infrared wavelengths,which are often adopted as activators for vari⁃ous luminescent materials.The theoretical studies on energy level structures and the luminescence mechanism of Bi^(3+)dopants can support the design and performance improvement of new luminescent materials.Here,after providing a brief summary of the calculation methods developed and the for⁃mula derived to bridge the data from calculations based on density functional theory,we presented the theoretical results from the first-principles calculations on several prototype systems and provided an interpretation of the reported experimental results.The configurational coordinate diagrams with structures and energies from first-principles calculations played a central role in the analyses.Four different types of excited states of Bi^(3+)ions are covered:the internal excitation of 6s16p1 electron con⁃figuration,the ligand-dopant charge transfer excitation of 6s26p1 plus a localized hole,the metal to metal charge transfer excitation of 6s1 plus a bound electron,and the inter-valent Bi^(2+)-Bi^(4+)state as an excited state of a Bi^(3+)pair.Great efforts have been done to provide detailed quantitative predictions on the spectroscopy of Bi^(3+)ions in solids.The results clearly show the role played by theoretical studies in designing and optimizing novel luminescent materials.In addition,the relationship of lumines⁃cent properties of Bi^(3+)ions with local coordination environment of dopant centers,band gap of hosts and defect levels was briefly discussed.
作者
楼碧波
尹民
LOU Bi-bo;YIN Min(School of Optoelectronic Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China;School of Physical Sciences,University of Science and Technology of China,Hefei 230026,China)
出处
《发光学报》
EI
CAS
CSCD
北大核心
2022年第9期1446-1458,共13页
Chinese Journal of Luminescence
基金
国家自然科学基金(52161135110,11974338)
国家科技部中国-波兰政府间科技合作交流项目(2020[15]/10)资助。
