Fine-grained phosphors for red-emitting mini-LEDs with high efficiency and super-luminance  

作　　者：Yu KANG Shuxing LI Rundong TIAN Guangzhu LIU Haorui DONG Tianliang ZHOU Rong-Jun XIE 

机构地区：[1]College of Materials Science and Engineering,Liaoning Technical University,Fuxin 123000,China [2]Fujian Provincial Key Laboratory of Surface and Interface Engineering for High Performance Materials,College of Materials,Xiamen University,Xiamen 361005,China [3]State Key Laboratory of Physical Chemistry of Solid Surfaces,Xiamen University,Xiamen 361005,China

出　　处：《Journal of Advanced Ceramics》2022年第9期1383-1390,共8页先进陶瓷（英文）

基　　金：This work is supported by the National Natural Science Foundation of China(Nos.51832005 and 52172157);the Fundamental Research Funds for the Central Universities(No.20720200075);Fujian Provincial Science and Technology Project(Nos.2020I0002 and 2021J01042).

摘　　要：Mini-LED backlights,combining color conversion materials with blue mini-LED chips,promise traditional liquid crystal displays(LCDs)with higher luminance,better contrast,and a wider color gamut.However,as color conversion materials,quantum dots(QDs)are toxic and unstable,whereas commercially available inorganic phosphors are too big in size to combine with small mini-LED chips and also have strong size-dependence of quantum efficiency(QE)and reliability.In this work,we prepare fine-grained Sr_(2)Si_(5)N_(8):Eu^(2+)-based red phosphors with high efficiency and stability by treating commercially available phosphors with ball milling,centrifuging,and acid washing.The particle size of phosphors can be easily controlled by milling speed,and the phosphors with a size varying from 3.5 to 0.7 mm are thus obtained.The samples remain the same QE as the original ones(~80%)even when their particle size is reduced to 3.2-3.5 mm,because they contain fewer surface suspension bond defects.More importantly,SrBaSi_(5)N_(8):Eu^(2+)phosphors show a size-independent thermal quenching behavior and a zero thermal degradation.We demonstrate that red-emitting mini-LEDs can be fabricated by combining the SrBaSi_(5)N_(8):Eu^(2+)red phosphor(3.5 mm in size)with blue mini-LED chips,which show a high external quantum efficiency(EQE)of above 31%and a super-high luminance of 34.3 Mnits.It indicates that fine and high efficiency phosphors can be obtained by the proposed method in this work,and they have great potentials for use in mini-LED displays.

关 键 词：Sr_(2)Si_(5)N_(8):Eu^(2+)-based phosphors particle size external quantum efficiency(EQE) thermal degradation mini-LED 

分 类 号：TN871[电子电信—信息与通信工程]