Li substituent tuning of LED phosphors with enhanced efficiency, tunable photoluminescence, and improved thermal stability

Solid-state phosphor-converted white light-emitting diodes (pc-WLEDs) are currently revolutionizing the lighting industry. To advance the technology, phosphors with high efficiency, tunable photoluminescence, and high thermal stability are required. Here, we demonstrate that a simple lithium incorporation in NaAlSiO4:Eu system enables the simultaneous fulfillment of the three criteria. The Li substitution at Al sites beside Na sites in NaAlSiO4:Eu leads to an enhanced emission intensity/efficiency owing to an effective Eu3+to Eu2+reduction, an emission color tuning from yellow to green by tuning the occupation of different Eu sites, and an improvement of luminescence thermal stability as a result of the interplay with Li-related defects. A pc-WLED using the Li-codoped NaAlSiO4:Eu as a green component exhibits improved performance. The phosphors with multiple activator sites can facilitate the positive synergistic effect on luminescence properties.

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High-efficiency fully concentrated Na3Eu(VO4)2 phosphor with excellent thermal stability for white light-emitting diodes

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-020-03840-7 ◽

2020 ◽

Vol 31 (15) ◽

pp. 12872-12879

Author(s):

Jiangcong Zhou ◽

Yanling Zhang ◽

Yao Yao ◽

Bo Wang ◽

Yiqing Lai ◽

...

Keyword(s):

Thermal Stability ◽

White Light ◽

High Efficiency ◽

Light Emitting Diodes ◽

Excellent Thermal Stability ◽

Light Emitting ◽

White Light Emitting Diodes

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Ultra-High Efficiency White Light Emitting Diodes

Japanese Journal of Applied Physics ◽

10.1143/jjap.45.l1084 ◽

2006 ◽

Vol 45 (No. 41) ◽

pp. L1084-L1086 ◽

Cited By ~ 166

Author(s):

Yukio Narukawa ◽

Junya Narita ◽

Takahiko Sakamoto ◽

Kouichiro Deguchi ◽

Takao Yamada ◽

...

Keyword(s):

White Light ◽

High Efficiency ◽

Light Emitting Diodes ◽

Light Emitting ◽

White Light Emitting Diodes

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Solid-State Carbon Dots-Based White Light-Emitting Diodes With Ultrahigh Color Rendering Index and Good Thermal Stability

IEEE Transactions on Electron Devices ◽

10.1109/ted.2021.3094495 ◽

2021 ◽

pp. 1-6

Author(s):

Luqiao Yin ◽

Yuxian Yan ◽

Huazhang Guo ◽

Liang Wang ◽

Huixin Xiu ◽

...

Keyword(s):

Thermal Stability ◽

Solid State ◽

White Light ◽

Carbon Dots ◽

Light Emitting Diodes ◽

Light Emitting ◽

Good Thermal Stability ◽

Color Rendering Index ◽

White Light Emitting Diodes ◽

Color Rendering

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Synthesis and Characterization of CaMgSi2O6 Activated by Eu2+

Materials Science Forum ◽

10.4028/www.scientific.net/msf.881.30 ◽

2016 ◽

Vol 881 ◽

pp. 30-34

Author(s):

Agatha Matos Misso ◽

Hermi F. Brito ◽

Lucas C.V. Rodrigues ◽

Vinicius R. Morais ◽

Chieko Yamagata

Keyword(s):

High Efficiency ◽

Low Cost ◽

Sol Gel ◽

Solid State Reactions ◽

Phase Identification ◽

Molten Salt Method ◽

Persistent Luminescence ◽

Light Emitting ◽

Fluorescent Lamps ◽

White Light Emitting Diodes

Rare earth silicate based MnMgSi2O5+n (M = Ca, Sr or Ba and n=1-2) phosphors, have attracted interest of researchers due to their high efficiency as a host, excellent thermal and chemical stability and high brightness adding to their low cost. These phosphors showed great potential in various applications such as fluorescent lamps, white light emitting diodes, and display components. High temperature solid-state reactions are usually employed to synthesize those compounds. This paper proposes an alternative method of obtaining nanophosphor host based on Eu-doped CaMgSi2O6 (CMS:Eu), persistent luminescence phosphor. Sol gel technique combined to a modified molten salt method was used. The resulted powder was calcined for 3h under an atmosphere of 5% H2 and 95% Ar2. Phase identification by XRD and the measurements of photoluminescence (PL) and photoluminescence excitation (PLE) were performed. Single phased CMS:Eu with persistent luminescence characteristics was prepared.

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Efficient and controllable photoluminescence in novel solid solution Ca1−xSrxHf4(PO4)6:Eu2+ phosphors with high thermal stability for white light emitting diodes

CrystEngComm ◽

10.1039/c8ce00898a ◽

2018 ◽

Vol 20 (31) ◽

pp. 4383-4394 ◽

Cited By ~ 22

Author(s):

Shuangyu Xin ◽

Miao Gao ◽

Chuang Wang ◽

Xuejiao Wang ◽

Ge Zhu ◽

...

Keyword(s):

Thermal Stability ◽

Solid Solution ◽

Quantum Efficiency ◽

White Light ◽

Light Emitting Diodes ◽

High Thermal Stability ◽

Photoluminescence Properties ◽

Light Emitting ◽

White Light Emitting Diodes

The tunable photoluminescence properties of (Ca,Sr)Hf4(PO4)6:Eu2+ solid solution phosphors with high thermal stability and quantum efficiency were investigated.

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