Synthesis and optical properties of highly efficient Na_(3)KMg_(7)(PO_(4))_(6):Eu^(2+)blue phosphor for full-spectrum white-light-emitting diodes:The role of Li_(2)CO_(3)flux  

作　　者：Zihao Wang Sisi Liang Chenyang Zhan Kunyuan Xu Jie Hu Dejian Chen Liping Song Haomiao Zhu 

机构地区：[1]School of Physics and Materials Science,Nanchang University,Nanchang,330000,China [2]Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou,341000,China [3]CAS Key Laboratory of Design and Assembly of Functional Nanostructures,and Fujian Key Laboratory of Nanomaterials,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou,350002,China [4]Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials,Xiamen Research Center of Rare Earth Materials,Haixi Institute,Chinese Academy of Sciences,Xiamen,361021,China

出　　处：《Journal of Rare Earths》2024年第7期1217-1223,I0001,共8页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(11974351)。

摘　　要：Full-spectrum phosphor-converted white-light-emitting diodes(pc-WLED)are emerging as a mainstream technology in semiconductor lighting.Nevertheless,high-performance blue phosphor which can be excited efficiently by a 400 nm NUV diode chip is still lacking.Herein,we present a blue-emitting Na_(3)KMg_(7)(PO_(4))6:Eu^(2+)phosphor synthesized by the solid-reaction method.Particularly,we find that the using of Li_(2)CO_(3)as flux can significantly improve the crystal quality and thus the emission efficiency of the phosphor.Meanwhile,the excitation peak of the phosphor shifts from 365 to 400 nm,which is pivotal for efficient NUV(400 nm)diode chip excitation.The practical Eu^(2+)concentration is also enhanced by using Li_(2)CO_(3)as flux,and the absorption efficiency is greatly increased.This phosphor exhibits superior PL thermal stability,namely retains 94%integrated photoluminescence intensity at 150℃of that at 25℃.As a result,the optimized phosphor shows an emission band peaked at 437 nm with a bandwidth of 40 nm and a high external photoluminescence quantum yield of 51.7%.Finally,a pc-WLED was fabricated by using NKMPO:Eu^(2+)blue,Sr_(2)SiO_(4):Eu^(2+)green,CaAlSiN_(3):Eu^(2+)red phosphors,and a 400 nm NUV diode chip.It shows a high color rendering index of R_(a)=96.4 and a correlated color temperature of 4358 K.These results prove that NKMPO:Eu^(2+)is a promising blue phosphor for full-spectrum WLED based on NUV diode chips.

关 键 词：Eu^(2+) Blue phosphor Na_(3)KMg_(7)(PO_(4))_(6) Full-spectrum white LEDs Rare earths 

分 类 号：TN312.8[电子电信—物理电子学] TQ422[化学工程]