Zhou Guojun, Liu Zhiyang, Huang Jinglong, Molokeev Maxim S, Xiao Zewen, Ma Chonggeng, Xia Zhiguo
The State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques, School of Materials Science and Technology, South China University of Technology, Guangzhou 510641, China.
Key Laboratory of Magnetic Molecules and Magnetic Information Materials (Ministry of Education), School of Chemistry and Material Science, Shanxi Normal University, Linfen 041004, China.
J Phys Chem Lett. 2020 Aug 6;11(15):5956-5962. doi: 10.1021/acs.jpclett.0c01933. Epub 2020 Jul 13.
Zero-dimensional (0D) Mn-based metal halides are potential candidates as narrow-band green emitters, and thus it is critical to provide a structural understanding of the photophysical process. Herein, we propose that a sufficiently long Mn-Mn distance in 0D metal halides enables all Mn centers to emit spontaneously, thereby leading to near-unity photoluminescence quantum yield. Taking lead-free (CHN)ZnMnBr ( = 0-1) solid solution as an example, the Zn/Mn alloying inhibits the concentration quenching that is caused by the energy transfer of Mn. (CHN)MnBr exhibits highly thermal stable luminescence even up to 150 °C with a narrow-band green emission at 518 nm and a full width at half maximum of 46 nm. The fabricated white light-emitting diode device shows a high luminous efficacy of 120 lm/W and a wide color gamut of 104% National Television System Committee standard, suggesting its potential for liquid crystal displays backlighting. These results provide a guidance for designing new narrow-band green emitters in Mn-based metal halides.
零维（0D）锰基金属卤化物作为窄带绿色发光体具有潜在的应用前景，因此深入了解其光物理过程的结构至关重要。在此，我们提出，0D金属卤化物中足够长的Mn-Mn距离能使所有Mn中心自发发光，从而实现接近100%的光致发光量子产率。以无铅（CHN）ZnMnBr（=0-1）固溶体为例，Zn/Mn合金化抑制了由Mn的能量转移引起的浓度猝灭。（CHN）MnBr即使在高达150°C时仍表现出高热稳定性发光，在518nm处有窄带绿色发射，半高宽为46nm。所制备的白光发光二极管器件显示出120lm/W的高发光效率和104%美国国家电视系统委员会标准的宽色域，表明其在液晶显示器背光源方面的潜力。这些结果为设计新型锰基金属卤化物窄带绿色发光体提供了指导。
