异价阳离子替代实现的金属卤化物CsCdCl_(3)的明亮宽带绿色发光  

Bright Broadband Green Photoluminescence of CsCdCl_(3) Metal Halides Achieved by Heterovalent Cation Substitution

作　　者：宋妍 王录 陈明星[3] 魏荣敏 李新慧 贾贞 夏明军[4] SONG Yan;WANG Lu;CHEN Mingxing;WEI Rongmin;LI Xinhui;JIA Zhen;XIA Mingjun(School of Chemical Engineering and Technology,North University of China,Taiyuan 038507,China;College of Chemistry and Chemical Engineering,Dezhou University,Dezhou 253023,China;Analytical Instrumentation Center of Peking University,Peking University,Beijing 100871,China;Key Laboratory of Functional Crystals and Laser Technology,Beijing Center for Crystal Research and Development,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]中北大学化学工程与技术学院,太原038507 [2]德州学院化学化工学院,德州253023 [3]北京大学分析测试中心,北京100871 [4]中国科学院理化技术研究所,人工晶体研究发展中心,中国科学院功能晶体与激光技术重点实验室,北京100190

出　　处：《人工晶体学报》2023年第2期307-314,共8页Journal of Synthetic Crystals

基　　金：山东省自然科学基金(ZR2020MF128,ZR2021MB059)。

摘　　要：全无机金属卤化物灵活多变的结构及优异的发光性能使其在固态光电子领域显示出重要的应用前景。本研究采用异价阳离子取代策略,用三价锑离子部分取代CsCdCl_(3)中的二价镉离子,促进自陷激子的产生,使CsCdCl_(3)∶Sb^(3+)产生了明亮的宽带绿色发光,中心波长为530 nm。机理研究结果表明,CsCdCl_(3)∶Sb^(3+)中相邻SbCl_(6)八面体被孤立,形成了低维电子构型,促进了Sb^(3+)局域化,实现了量子效率最高为95.5%的高效发光。此外,尽管CsCdCl_(3)和RbCdCl_(3)均属于ACdCl_(3)(A为碱金属家族),但它们的晶体结构明显不同。RbCdCl_(3)属于正交晶系,空间群为Pnma;CsCdCl_(3)属于六方晶系,空间群为P63/mmc。CsCdCl_(3)的结构对称性大于RbCdCl_(3),其晶体结构偏离立方相的扭曲程度比RbCdCl_(3)小,导致CsCdCl_(3)∶Sb^(3+)比RbCdCl_(3)∶Sb^(3+)有较小的斯托克斯位移,并造成发射光谱的蓝移。本工作不仅为异价阳离子取代设计新的发光材料提供了方法,而且为通过晶体结构对称调控金属卤化物的发光性能提供了思路。All-inorganic metal halides have shown significant applications in solid-state optoelectronics because of their flexible structures and impressive fluorescence emissions. In this study, a heterovalent cation substitution strategy was used to partially replace the divalent cadmium ions in CsCdCl_(3)with trivalent antimony ions to promote the production of self-trapped excitons, resulting in a bright broadband green photoluminescence of CsCdCl_(3)∶Sb^(3+)with a central wavelength of 530 nm. Mechanism researches results show that the adjacent SbCl_(6)octahedra in CsCdCl_(3)∶Sb^(3+)are isolated, forming a low-dimensional electronic configuration that promotes Sb^(3+)localization and achieves efficient photoluminescence with a quantum efficiency of up to 95.5%. Furthermore, although both CsCdCl_(3)and RbCdCl_(3)belong to ACdCl_(3)(A is an alkali metal family), they have distinctly different crystal structures. RbCdCl_(3)crystallizes in the orthorhombic crystal system with space group of Pnma;while CsCdCl_(3)crystallizes in the hexagonal phase crystal system with space group of P63/mmc. The structural symmetry of CsCdCl_(3)is higher than that of RbCdCl_(3), indicating that its crystal structure is less distorted away from the cubic phase than that of RbCdCl_(3), resulting in a smaller Stokes shift and corresponding blue shift of the emission spectrum in CsCdCl_(3)∶Sb^(3+)than in RbCdCl_(3)∶Sb^(3+). This work not only provides a method for designing new photoluminescence materials by heterovalent cation substitution but also paves an avenue for modulating the luminescent properties of metal halides through crystal structure symmetry.

关 键 词：金属卤化物 异价阳离子取代 自陷激子 高量子效率 镉 绿色发光 

分 类 号：O641[理学—物理化学]