Design of luminescence in(Sr,Gd)Li(Al,Mg)_(3)N_(4):Eu^(2+)deep red phosphors via crystal field engineering for full-spectrum WLEDs  

作　　者：Qing Lin Tongyu Gao Yuanhong Liu Ronghui Liu Siwei Chen Xiaole Ma Chunlei Zhao 

机构地区：[1]National Engineering Research Center for Rare Earth,GRINM Group Co.,Ltd.,Beijing 100088,China [2]GRIREM Advanced Materials Co.,Ltd.,Beijing 100088,China [3]General Research Institute for Nonferrous Metals,Beijing 100088,China

出　　处：《Journal of Rare Earths》2023年第8期1127-1134,I0001,共9页稀土学报（英文版）

基　　金：supported by the National Key Research and Development Program of China(2021YFB3500402)。

摘　　要：Red phosphor,with longer wavelength,is highly desirable for full-spectrum WLEDs.Targeted deep red phosphors(Sr,Gd)Li(AI,Mg)_(3)N_(4):Eu^(2+)were designed from the initial model of SrLiAl_(3)N_(4):Eu^(2+)by structural modification.The correlations among structural evolution,crystal-field environment,and luminescence properties were elucidated.Replacing Sr^(2+)with Gd^(3+)in(Sr,Gd)LiAl_(3)N_(4):Eu^(2+)leads to the enhanced crystal field splitting,larger Stokes shift,and increased structural polyhedron distortion differences,consequently resulting in spectral red-shift and broadening.For further spectral tuning,Mg,with lower electronegativity,was also introduced to modify the local crystal structure,consequently resulting in a further red-shift towards 675 nm and enhanced photoluminescence intensity in(Sr,Gd)Li(AI,Mg)_(3)N_(4):Eu^(2+).What’s more,w-LEDs were fabricated by using blue LED chip,blue,green,red and deep red((Sr,Gd)Li(Al,Mg)_(3)N_(4):Eu^(2+))phosphors whose color rendering index were Ra 96.0 and R997.7.All above results demonstrate that the partial replacements of Sr^(2+)by Gd^(3+)and Al^(3+)by Mg^(2+)are effective methods for spectral modulation and(Sr,Gd)Li(AI,Mg)_(3)N_(4):Eu^(2+)phosphors are suitable for highquality full-spectrum WLEDs.

关 键 词：Full-spectrum WLEDs Structural modulation Deep red phosphor Rare earths 

分 类 号：TQ422[化学工程] TN312.8[电子电信—物理电子学]