Advanced Optical Materials
·
2022
·Vol. 10
·期 7
·2102141
·
IF 10.05
Hong Ming,Yifei Zhao,Yayun Zhou,Maxim S. Molokeev,Yuanjing Wang,Shuai Zhang,Enhai Song,Shi Ye,Zhiguo Xia,Qinyuan Zhang
The design and discovery of Mn 4+ -activated fluoride phosphors that can secure both high luminescence efficiency and short fluorescence lifetime simultaneously are crucial and urgent for constructing high-quality wide-color gamut (WCG) backlight display applications. Herein, a series of brand-new Mn 4+ -activated narrow-band red-emitting phosphors with both high external quantum efficiency (EQE, >50%) and short fluorescence lifetime (τ ≤ 3.8 ms) are designed by introducing Mn 4+ into newfound tetramethylammonium (Me 4 N)-based organometallic fluoride (Me 4 N) 2 B F 6 ( B = Ge, Ti, Zr) hosts. These intriguing properties of Mn 4+ arise from the larger steric hindrance of (Me 4 N) + cations and low local structure symmetry in the 0D (Me 4 N) 2 B F 6 , as verified by the structural and spectral analyses. (Me 4 N) 2 GeF 6 :Mn 4+ , as a representative, shows a high EQE of ≈64.6% and a short lifetime of ≈3.78 ms. A prototype projector with superb performance is assembled by employing a remote (Me 4 N) 2 GeF 6 :Mn 4+ -based white light-emitting diode with high luminous efficiency (≈143.09 lm W −1 ) and WCG (≈112.02% National Television System Committee (NTSC)) to demonstrate their great potentials for backlight applications. The research brings up a promising alternative as the host materials for Mn 4+ -doped fluoride phosphors and provides a deeper understanding on the correlation between structure and luminescence.
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
·
2019
·
IF 4.175
Yuanjing Wang,Yayun Zhou,Enhai Song
Mn 4+ -activated fluoride red phosphors have a bright prospect for improving the warm white light-emitting diodes (W-LEDs) performances, whereas there remains some challenges in synthesis, such as reducing the consumption of toxic HF and improving Mn 4+ doping efficiency. Herein, a new phosphor (NH 4 ) 2 NaScF 6 :Mn 4+ (NNSFM) was synthesized by an ammonium salt conversion method, which can effectively reduce HF consuming, enhance reaction rate and doping efficiency. The synthesis mechanism, luminescence properties and W-LEDs performances of the as-synthesized NNSFM have been investigated. Moreover, the lattice structure and doping position have been investigated in detail by the density functional calculations (DFT), which show that Mn 4+ could occupy the Sc 3+ crystallographic site in this structure and simultaneously produce a Na vacancy ( V Na ' ) for charge compensation. Using the NNSFM as red-light component, a warm W-LED device with a high color rendering index (CRI, Ra = 80.6) and low correlated color temperature (CCT = 3006 K) has been achieved. This work presents a new Mn 4+ doped fluoride red phosphor and also develops an environmentally friendly strategy for synthesizing Mn 4+ doped fluoride phosphors.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
CHEMICAL PHYSICS
·
2024
·
IF 2
Qian Du,Yu-Guo Yang,Xiao-Na Shen,Yuan-Yuan Zhang,Shen-Ao Hu,Bing Liu,Qing-Gang Li,Xian-Shun Lv,Hua-Jian Yu,Lei Wei,Cheng-Cheng Qiu,Jing-Feng Li,Rui Zhang,Xu-Ping Wang
Sr(La, Y)Ga 3 O 7 : Mn 4+ phosphors were prepared by sintering at 1400 ℃. The structural characteristics of phosphors were analyzed by means of XRD measurements. Surface compositions and chemical state of the elements were gained from XPS measurements. And the vibration and rotation information of the molecular structure was detected in Raman spectra. The phosphors show characteristic excitation spectrum of Mn 4+ , which puts down to the electronic transition of 4 A 2g → 4 T 1g and 4 A 2g → 4 T 2g . Exciting at 380 nm, the phosphors emit deep red light resulting from the 2 E g → 4 A 2g transition. The Y 3+ substitution influences crystal structure and photoluminescence performance obviously. The incorporation of a small amount of Y 3+ reduces the cell volume and induces impurity phase of Y 3 Ga 5 O 12 in all prepared phosphors. The band peaking at 715 nm decreases highly and the band becomes stronger when x ≥ 0.4.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Chemistry
·
2023
·
IF 7.3
Haonan Yu,Jingming Chan,Balaji Devakumar,Xiaoyong Huang
High-efficiency far-red emitting phosphors with an emission peak of around 730 nm are urgently needed for indoor plant growth light-emitting diode (LED) lighting. In this article, we report on the synthesis, crystal structure, and luminescence properties of a new highly efficient Mn 4+ ion-activated Li 3 La 3 W 2 O 12 (LLWO) far-red emitting phosphor. A group of LLWO:Mn 4+ phosphors doped with different Mn 4+ ion concentrations have been prepared via the conventional high-temperature solid-state reaction route. X-ray diffraction Rietveld refinement reveals that the LLWO:Mn 4+ phosphor has the monoclinic structure with space group P2 1 /n , along with lattice parameters of a = 5.5396 Å, b = 5.6026 Å, c = 7.8802 Å, α = γ = 90°, β = 90.0988°, and V = 244.57 Å 3 . Interestingly, LLWO:Mn 4+ phosphors can generate bright narrowband far-red emission in the 650–800 nm wavelength range peaking at 719 nm due to the spin- and parity-forbidden 2 E g → 4 A 2g transition of Mn 4+ ions, matching well with the absorption spectrum of phytochrome P FR . The excitation spectrum monitored at 719 nm has a broad excitation band with the range from 250 to 550 nm centered at 339 nm and 472 nm, indicating that LLWO:Mn 4+ phosphors could be efficiently pumped by both ultraviolet and blue LED chips. The highest far-red emission is achieved for the sample doped with 1.2 mol% Mn 4+ ion, and this optimal LLWO:1.2%Mn 4+ sample shows a high internal quantum efficiency of 88.4% and a decay lifetime of 2.289 ms. Commission Internationale de l’Eclairage (CIE) color coordinates of LLWO:1.2%Mn 4+ are determined to be (0.7326, 0.2674). Besides, the crystal field analysis and temperature-dependent emission spectra of the as-prepared samples have been investigated in detail. The emission intensity of LLWO:1.2%Mn 4+ sample at 423 K remains about 40% of that at 303 K. Finally, a LED device is fabricated by integrating the LLWO:1.2%Mn 4+ phosphors and a 460 nm blue LED chip, which shows bright blue and far-red dual emission bands under 20–300 mA driving currents. This work demonstrates that these newly developed far-red emitting LLWO:Mn 4+ phosphors have excellent application prospects in plant growth LED lighting.
研究领域:
材料科学
·
园艺学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2021
·
IF 4.641
Renping Cao,Weijun Zhang,Ting Chen,Yunfei Zheng,Hui Ao,Zhiyang Luo,Shikun Xie,Huijun Wan
Ba 2 La 2 ZnW 2 O 12 :xMn 4+ (BLZWO:xMn 4+ ) (0 ≤ x ≤ 1.2 mol%) are prepared via the solid state reaction method under air conditions. The crystal phases and optical properties of all samples are investigated. The yellow emission of BLZWO is observed with the chromaticity coordinates (0.3940, 0.4389), and its emission spectrum covers the region from 380 to 810 nm owing to the W 6+ - O 2− transition. When the excitation wavelength is 344 nm, BLZWO:xMn 4+ show an adjustable photo-luminescence characteristic by altering the Mn 4+ concentration owing to the energy transfer from [WO 6 ] group to Mn 4+ ions. With excitation at 514 nm, BLZWO:xMn 4+ only show red emission. The excitation spectrum of BLZWO:Mn 4+ with peaks at 344 and 514 nm is in the region from 210 to 600 nm and its emission spectrum with peak at 704 nm are observed in the range of 625–800 nm. The lifetimes of BLZWO:xMn 4+ reduce successively with adding Mn 4+ concentration. The results are good for the basic research on luminescence characteristics of Mn 4+ ion.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2020
·
IF 4.825
Zhaowu Wang,Haipeng Ji,Jian Xu,Xinghui Hou,Jumpei Ueda,Setsuhisa Tanabe,Shasha Yi,Ying Zhou,Deliang Chen
A single-crystalline defect-less phosphor is desired for efficient luminescence of the therein doped optical activators. In this paper, microsized MgAl2O4:Mn4+ single-crystal phosphors with bright red luminescence were grown in molten LiCl salt at 950 °C, for application in blue LED pumped white lighting. By comparing the phosphor formation from various Mg2+- and Al3+-bearing sources, both the template-formation and the dissolution-diffusion processes were evidenced to account for the formation of the microsized MgAl2O4:Mn4+ crystallites. Using nano γ-Al2O3 as the Al3+-bearing precursor, the uniform MgAl2O4:Mn4+ microcrystallites with a {111} planes-exposed tetragonal bipyramid morphology were obtained. The photoluminescence property was studied at various temperatures, and Mg ↔ Al anti-site disorder induced luminescence broadening was discussed. The Mn4+2Eg → 4A2g transition in MgAl2O4 shows a quite short luminescence wavelength peaking at 651 nm and ultrabroadband emission extending to 850 nm. The luminescence is relatively robust against thermal effect with relatively high thermal quenching temperature of 400 K and activation energy of 0.23 eV. Employing the red-emitting MgAl2O4:Mn4+ crystallites, blue LED pumped white lighting prototypes were fabricated which simulate the solar-like spectrum and show neutral to warm white.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Laser & Photonics Reviews
·
2023
·Vol. 17
·期 8
·2200940
·
IF 11
Yiyang Liu,Rong Zhang,Kaiyi Yan,Jian-Feng Sun
The mineral structure-inspired discovery of red phosphors has become a research hotspot that can help compensate for the missing red components in cold white light-emitting diodes (WLEDs). Herein, first the feldspar-type structure is utilized to develop narrowband red-emitting CaAl 2 Si 2 O 8 :Mn 4+ /Mn 4+ , Mg 2+ phosphors. Rietveld refinement results confirm the Mn 4+ occupation of the distorted [Ca1O 6 ] octahedron, resulting in a strong nephelauxetic effect, and thus exhibits bright red luminescence with a narrow full width at half maximum (43 nm). Compared with CaAl 2 Si 2 O 8 :Mn 4+ , the fluorescence intensity of CaAl 2 Si 2 O 8 :Mn 4+ , Mg 2+ is further enhanced by up to 210% owing to the decreasing nonradiative decay rate from 2 E g excited state, which weakens the concentration quenching effect resulting from energy migration along the adjacently aggregated Mn 4+ . CaAl 2 Si 2 O 8 :Mn 4+ , Mg 2+ shows preferable thermal stability with an ultrahigh quantum efficiency (90.3%), surpassing other current Mn 4+ -doped oxide phosphors and UCr 4 C 4 -type nitride phosphors. A fabricated prototype WLED obtains ideal warm white light with a low correlated color temperature (3081 K) and a wide color gamut covering 112% of the National Television System Committee standard. Guided by natural mineral-type structural prototypes, this study demonstrates the possibility of designing a uniquely distorted local structure to achieve a superior luminescence performance of Mn 4+ for warm WLEDs.
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
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Zhongfa Li,Wenjun Zhang,Chengyue Xin,Zihan Chen,Jian Sheng
Mn ions in different valence states can emit light of different colors in an octahedral coordination environment, which is conducive to the development of a single matrix with multi-color luminescence and applications in the field of anti-counterfeiting. The dual mode multi-color luminescent material CaSb 2 O 6 : Mn has been successfully synthesized using a single Mn source in the atmosphere. The CaSb 2 O 6 matrix itself can also absorb 285 nm UV light, emit blue light, and show a long afterglow phenomenon. Both Mn 4+ and Mn 2+ ions will appear in the [SbO 6 ] octahedra, whether the Mn source adopts MnCO 3 or MnO 2 . The Mn 4+ ion exhibits red emission upon UV excitation at 347 nm. The Mn 2+ ion can emit a bright green light at 285 nm excitation while exhibiting a long afterglow phenomenon. In this study, the Mn 2+ doped octahedron showed unique green emission and broadens the range of its photoluminescence (PL) wavelength. The performance of the material's long afterglow properties on the digital codes demonstrates its potential for dynamic anti-counterfeiting.
研究领域:
材料科学
·
光学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2021
·Vol. 50
·期 20
·7017-7025
·
IF 4.39
Yonghui Xu,Liang Zhang,Langping Dong,Shuwen Yin,Xiudi Wu,Hongpeng You
Novel single-doped and codoped SrGd2Al2O7-based (SGA) phosphors with tunable emission were synthesized via the solid-state reaction approach. The optimal SGA:0.0008Mn4+ phosphor presents an emission band peaking at 709 nm and shows great red luminescence properties. With the incorporation of Nd3+/Yb3+ into SGA:0.0008Mn4+, an efficient energy transfer Mn4+ → Nd3+/Yb3+ was observed. When Nd3+ and Yb3+ were codoped into SGA:0.0008Mn4+, an energy transfer mechanism from Mn4+ to Nd3+ to Yb3+ was found on the basis of the energy transfer mediation of Nd3+ connecting the Mn4+ and Yb3+ luminescent centers. It results in a strong near-infrared emission in the spectral region of high response of c-Si solar cells, which suggests a potential approach to improve the energy conversion efficiency of c-Si solar cells. The findings offer a novel route to design new down-conversion luminescent materials for the c-Si solar cells.
研究领域:
材料科学
·
无机化学
·
光电子学
·
新能源材料
·
固体物理
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Qingdong Gou,Junwei Jiang,Hui Ao,Siling Guo,Ting Chen,Xiaochun Li,Jingjing Duan,Renping Cao
Light can improve the growth and development of most plants, and the red/deep-red light in the 600–760 nm region is very good for phytochrome red and phytochrome far-red of plants, causing a great interest in the research and development of the deep-red-emitting luminescence materials. In this work, a pure phase LiAlSi 2 O 6 :Mn 4+ with monoclinic crystal structure and only luminous center (Mn 4+ ) is synthesized successfully in air. The excitation spectrum of LiAlSi 2 O 6 :Mn 4+ covers the region from 220 to 550 nm owing to the O 2− - Mn 4+ charge transfer and the 4 A 2g → 4 T 1g and 4 T 2g transitions of Mn 4+ . We observe the deep-red emission of LiAlSi 2 O 6 :Mn 4+ with emission peak at ∼663 nm in the range of 600–850 nm due to the transitions 2 E g → 4 A 2g of Mn 4+ and analyze the luminous mechanism. The optimal doping concentration of Mn 4+ (0.1mol%) is determined by the concentration dependent emission spectra. We analyze the concentration quenching mechanism and investigate the lifetimes of LiAlSi 2 O 6 :Mn 4+ with different Mn 4+ concentration. The good thermal stability of LiAlSi 2 O 6 :Mn 4+ is confirmed via the temperature dependent emission spectra. The potential applications of LiAlSi 2 O 6 :Mn 4+ in plant growth LED lighting are estimated by comparison of spectral properties of LiAlSi 2 O 6 :Mn 4+ and plant.
研究领域:
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2021
·
IF 3.599
Zuizhi Lu,Yingbin Meng,Hua Fan,Jiangying Lu,Xiaoying Zhong,Yingjun Ou,Hairong Mo,Liya Zhou
Mn 4+ -doped double-perovskite LaTiSbO 6 (LTS) phosphors were fabricated via traditional high-temperature sintering reaction. The crystal structure, composition , and luminescent properties of the LTS:Mn 4+ phosphors were studied. The PLE spectrum presents two broad bands that are centered at 356 and 475 nm, and they match the UV and blue chips. A broad emission band that is centered at 685 nm is presented in the PL spectrum. The quantum efficiency is 21.3%. A red light LED device was also fabricated with LTS:0.007Mn 4+ phosphor and an InGaN chip (465 nm). The CCT, CRI, and luminous efficiency of the LED are 4215 K, 73.4, and 62.1 Im/W, respectively. The LED spectrum meets the needs of plant growth in blue and red light. Therefore, the LED fabricated by LTS:Mn 4+ phosphor is a potential light source for plant growth.
研究领域:
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2021
·
IF 3.08
Xiaoyi Liu,Haiping Xu,Yunxiao Zhang,Zhendong Fu,Feng Hong,Ge Pang,Guixia Liu,Dan Li,Xiangting Dong,Jinxian Wang
Chrysanthemum-like K 2 LiAlF 6 :Mn 4+ phosphors were synthesized by simple co-precipitation method without using HF. The K 2 LiAlF 6 :Mn 4+ phosphor can be effectively excited through blue light at 465 nm, then produces sharp red-light emission near 634 nm. The luminescence quenching of Mn 4+ is caused by the d-d interaction between Mn 4+ ions. The effects of surfactant and lithium source on the luminescent properties of K 2 LiAlF 6 :Mn 4+ phosphors were discussed. Mn 4+ is located in a strong crystal field environment in the K 2 LiAlF 6 matrix and its emission mechanism is discussed. Warm white light emitting diode (WLED) device, which is fabricated by coating a certain proportion mixture of yellow YAG:Ce 3+ phosphor and red K 2 LiAlF 6 :5%Mn 4+ phosphor on the blue GaN chip, has low correlation color temperature (CCT = 3588 K), high color rendering index (R a = 90.8) and good electroluminescence stability under different currents. These properties illustrate that K 2 LiAlF 6 :5%Mn 4+ phosphor is a promising red light emitting material.
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
危险品化学品经营许可证（带存储）