JOURNAL OF RARE EARTHS
·
2021
·
IF 3.712
Jiannan Jia,Mengting He,Jun Wan,Yuting Zhang,Hai Guo,Xianping Fan,Xusheng Qiao,Shiguo Chen
With narrow red photoluminescence (PL) bands, tetravalent Mn 4+ doped phosphors show promising prospect in commercial application to effectively expand color gamut of phosphor converted LED displays. Here, we report a type of Sr 2– z Mg 1+ y Y z Al 22– x O 36 : x Mn 4+ phosphors with regular cage-like micro-spherical morphologies. The micron size spherical precursors were synthesized with a propylene oxide (PO) driven fast sol–gel method. The cage -like spherical morphology is beneficial to efficiently trapping much incident light to enhance the PL of the phosphors. Being calcined at 1300 ° C, Sr 2 MgAl 21.978 O 36 :0.022Mn 4+ only exhibits the internal quantum efficiency (IQE) of 24.91%. With the Mg 2+ -Mn 4+ codoping and Y 3+ /Sr 2+ substituting strategies, to fulfill charge balance and produce John-Teller distortion, IQE of Sr 2– z Mg 1+ y Y z Al 22– x O 36 : x Mn 4+ can be further improved up to 36.45%. The CIE color coordinates of Sr 2– z Mg 1+ y Y z Al 22– x O 36 : x Mn 4+ under near ultraviolet excitation can be stably fixed to (0.723, 0.227) at deep red region. It thus finds a potential application as pc-LED display with much broader color gamut than that of the NTSC standard. Therefore, Sr 2– z Mg 1+ y Y z Al 22– x O 36 : x Mn 4+ micron size spheres can be employed as promising red phosphors for high performance LED displays.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2017
·Vol. 29
·期 1
·124-129
·
IF 2.019
Niu Pengfei,Liu Xiaohua,Wang Yiru,Zhao Weiren
Ba 2 LaV 3 O 11 :Eu 3+ phosphors were firstly synthesized by the traditional solid-state reaction method at 1100 °C. Their luminescence properties were investigated by photoluminescence excitation and emission spectra. The excitation spectrum shows a broad band centered at about 275 nm in the region from 200 to 370 nm, which is attributed to an overlap of the charge transfer transitions of O 2− → V 5+ and O 2− → Eu 3+ . The phosphors exhibit the red emissions of Eu 3+ and the emission intensity ratio of 5 D 0 → 7 F 2 to 5 D 0 → 7 F 1 is dependent on the Eu 3+ concentration due to an environment change about Eu 3+ ions. Concentration quenching occurs at 30 mol% in the phosphors and exchange interaction is its main mechanism. Ba 2 LaV 3 O 11 :Eu 3+ displays tunable CIE color coordinates from yellow orange to red depended on Eu 3+ content, which may have a potential application for illuminating and display devices.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Pengjun Zhang,Yifei Xu,Shuwei Hao,Chongqiang Zhu,Chunhui Yang
The conventional random co-doping of Tb 3+ and Eu 3+ leads to spatial separation that severely limits energy transfer efficiency between these ions, which is critical for minimizing non-radiative losses in white LEDs. To address the limitation, we designed BaTb 4- x Si 3 O 13 : x Eu 3+ , breaking through the bottleneck by occupying Tb 3+ sites with Eu 3+ . Rietveld refinement and ionic radius analysis confirmed site occupancy selectivity, enabling 71.59 % Tb 3+ →Eu 3+ energy transfer efficiency, which is higher than conventional random doping systems. Under 380 nm excitation, the phosphor yielded red emission with CIE coordinates of (0.6153,0.3838) and 86.64 % color purity, and exhibited exceptional thermal stability with 70 % intensity retention at 473 K. Fabricated wLEDs using a NUV chip with commercial blue phosphor, green phosphor, and the developed phosphor produced warm white light with a correlated color temperature of 4519 K and CIE coordinates of (0.3478, 0.3868), achieving a high color rendering index of 87.4. These results demonstrate BaTb 4 Si 3 O 13 :Eu 3+ as a highly promising red phosphor candidate for solid-state lighting applications.
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·
IF 2.7
Feiyan Xie,Junqiang Gu,Dekang Xu,Qiancheng Xiong,Jinyu Yang,Xiangjian Ou,Dawei Wen
Research into red phosphors with a high color rendering index is particularly compelling, given the absence of a red component in the spectrum of commercial pc-WLEDs, which combine blue LED chips with yellow-emitting YAG:Ce3+ phosphors. Herein, we reported a novel Eu3+ activated Ca3Zn3Te2O12 red-emitting phosphor, synthesized using a conventional high-temperature solid-phase method. The phase and crystal structures were analyzed by powder X-ray diffraction and Rietveld refinement. The optimal excitation peak of the Ca3Zn3Te2O12:Eu3+ phosphor was located at 395 nm, matching those of conventional commercial near-ultraviolet chips. In addition, the Ca3Zn3Te2O12:9%Eu3+ phosphor exhibited good thermal stability, with an activation energy of 0.267 eV, and the CIE color coordinates hardly changed with temperature. Ultimatel, a high-quality white LED device was fabricated by combining Ca3Zn3Te2O12:9%Eu3+ red phosphor, a commercial BaMgAl10O17:Eu2+ blue phosphor, and(Ba,Sr)2SiO4:Eu2+ green phosphor with a 395 nm near-UV chip. Despite a substantial increase in the input current from 20 to 320 mA, the white-LED maintained a stable color rendering index of around 80, highlighting its consistent performance. These results indicated that Eu3+ activated Ca3Zn3Te2O12 phosphors are promising red emission candidates for white LEDs pumped by near ultraviolet chips.
研究领域:
材料科学
·
光电技术
·
光子学
✓ 已验证
产品关联
DOI
高影响因子
ZEITSCHRIFT FUR NATURFORSCHUNG SECTION A-A JOURNAL OF PHYSICAL SCIENCES
·
2023
·Vol. 78
·期 11
·1061-1067
·
IF 1.8
Arif Ullah,Jinghao Zhuang,Zheng Liu,Xiaozhan Yang,Wenlin Feng
In this work, the phosphors of Eu 3+ ions doped Ba 2.9 Sr 0.1 WO 6 were successfully synthesized by the high-temperature solid-state method. The luminescence properties, including the emission and excitation spectra, fluorescent lifetimes, and CIE chromaticity coordinates were characterized. The crystal structure and composite of the samples were investigated by XRD (X-ray diffraction), and HRTEM (high-resolution transmission electron microscope). The emission spectra consist of the characteristic peak of Eu 3+ excitation at 393 nm; the leading emission peak at 618 nm can be ascribed to the transition of 7 F 0 → 5 L 6 . The optimal red emission is achieved by 2 % Eu 3+ doping. This red Ba 2.9 Sr 0.1 WO 6 : Eu 3+ has good luminescent properties and may have potential application in white LEDs.
研究领域:
材料科学
·
光电材料
·
荧光粉材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）