JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Lei Fu,Di Wu,Yanfei Xiao,Wanfang Zou,Jinfen Kuang,Yan Liang,Fu Du,Jiaqing Peng,Xinyu Ye
Blue phosphor Sr 5−x-y R y (PO 4 ) 3 Cl:xEu 2+ (R = La, Gd, Lu) was prepared via solid-state reaction process, in which R 3+ replaces part of Sr 2+ ions in the matrix to benefit Eu 2+ luminescence. The change of Eu 2+ /Eu 3+ values were studied by XPS , and the results shown that the incorporation of R 3+ in the matrix resulted in the values increase of Eu 2+ /Eu 3+ . And substitute R 3+ non-equivalently for Sr 2+ , the modified Sr 5−x-y R y (PO 4 ) 3 Cl:xEu 2+ phosphors show better luminescence intensity and thermal stability. The emission intensity of Sr 4.72 Lu 0.2 (PO 4 ) 3 Cl:0.08Eu 2+ is 1.97 times of Sr 4.95 (PO 4 ) 3 Cl:0.05Eu 2+ . Moreover, the thermal quenching of Eu 2+ photoluminescence could be reduced. Compared to the commercial BAM:Eu 2+ phosphor, the stabilities of all Sr 4.72 R 0.2 (PO 4 ) 3 Cl:0.08Eu 2+ (R=La 3+ , Gd 3+ and Lu 3+ ) phosphors are better than that of BAM:Eu 2+ at the temperatures below 100 °C. The luminescent intensity of Sr 4.72 Lu 0.2 (PO 4 ) 3 Cl:0.08Eu 2+ maintains 95% while BAM:Eu 2+ is only 88% of the initial intensity at 150 °C. By combining Sr 4.72 Lu 0.2 (PO 4 ) 3 Cl:0.08Eu 2+ , Y 3 (Al,Ga) 5 O 12 :Ce 3+ and CaAlSiN 3 :Eu 2+ with 400 nm near-ultraviolet LED chip, a white-light-emitting diode was obtained. The fabricated WLED device with CIE color coordinates x = 0.3896, y = 0.3788, low CCT (3775 K) and high Ra (95.1), has enormous potential application in full-spectrum lighting field.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2025
·
IF 4.2
Tao Wei,Lei Xu,Duanduan He,Heyun Xu,Fei Long,Chaoyong Deng,Xucheng Li
A series of Eu 2+ -activated β-Ca 3 (PO 4 ) 2 -type Ca 9 MgNa(PO 4 ) 7 phosphors were successfully synthesized via high-temperature solid-state reaction. The substitution effects of Zn 2+ for Mg 2+ and Li + for Na + on the local coordination environments and luminescence characteristics of Eu 2+ were systematically investigated. The results demonstrate that Eu 2+ ions predominantly occupy the Ca1/Ca2, Ca3, and Na sites in Ca 9 MgNa(PO 4 ) 7 , corresponding to emission peaks at blue(1), blue(2), and green, respectively. Zn 2+ substitution for Mg 2+ induces lattice expansion, which reduces the occupancy probability of Eu 2+ at Ca1/Ca2 sites while lowering the formation energy of Ca3 sites, thereby significantly enhancing Ca3 and Na + site emissions but reducing Ca1/Ca2 site intensity. Subsequent Li + substitution for Na + causes contraction of the Li/NaO 6 polyhedra, reducing the capacity of the Na sites to accommodate Eu 2+ . Concurrently, the adjacent Ca(3)O 9 polyhedra undergo expansion, promoting preferential Eu 2+ occupancy at the Ca3 sites and consequently enhancing the emission intensity at blue(1).
研究领域:
材料化学
·
无机化学
·
发光材料
·
固体物理
·
光学材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2023
·Vol. 11
·期 6
·2153-2161
·
IF 6.4
Tao Hu,Zelong Jiang,Bo Wang,Ting Yu,Dawei Wen,Qinguang Zeng,Yan Gao
Fine control of the photon emission of Eu2+ activated luminescent materials is essential for advanced optoelectronic applications. However, it remains difficult to design blue light excitable Eu2+ doped oxide red phosphors due to the ionicity of the oxide ions. Herein, we have mechanistically demonstrated that an Eu2+ incorporated CaYGaO4 phosphor exhibits efficient red emission at 650 nm, as a result of the Eu2+ 4f65d1 electronic state experiencing strong crystal field splitting. DFT calculations reveal that the Eu2+ ion is energetically favored in the octahedral Ca2+ site, which is responsible for the fascinating optical properties. We have also demonstrated a strategy of post thermal annealing for improving both the emission efficiency and thermal emission quenching properties of this newly developed red phosphor. By employing the as-fabricated phosphor as a red color convertor, a warm white lighting device with a high color render index of 89.7 and low corrected color temperature of 3780 K was constructed. Our findings not only provide a promising red phosphor candidate for lighting of excellent quality, but also help to stimulate new routes for designing and improving the photon emission of rare-earth luminescent materials.
研究领域:
材料科学
·
光电技术
·
发光材料
·
照明技术
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·Vol. 35
·期 2
·2412480
·
IF 18.5
Ming Zhao,Yeping Ge,Yurong Li,Xiaoyan Song,Xinping Zhang
The advancement of Eu 2+ -activated luminescent materials tailored to exhibit a range of properties is crucial for addressing the specific demands of various application fields. However, the lack of suitable lattice sites in numerous compounds for stable Eu 2+ incorporation restricts their potential for diverse optical properties. Herein, a facile strategy of carbon and hydrogen coreduction utilizing graphite crucibles is proposed to effectively achieve the impressive luminescence of Eu 2+ at trivalent Y sites in Rb 3 Y(PO 4 ) 2 :Eu phosphors. Rb 3 Y(PO 4 ) 2 :Eu exhibits blue-violet emission when Eu 2+ predominantly occupies the Rb1 and Rb2 sites. Inspiringly, by facilitating the reduction of more Eu 3+ to Eu 2+ , a yellow emission band at 550 nm arising from Eu 2+ at Y sites emerges, enabling the realization of single-component white-emitting and yellow-emitting Rb 3 Y(PO 4 ) 2 :Eu phosphors. The diverse luminescent properties of Rb 3 Y(PO 4 ) 2 :Eu expand its potential applications in different white light source devices and optical thermometry. This work presents an innovative synthetic strategy to develop remarkable Eu 2+ luminescence at trivalent cation sites, thereby broadening the optical properties of the material and enabling multifunctional applications.
研究领域:
材料科学
·
发光材料
·
固态化学
·
光学性质
·
荧光粉技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）