Journal of Materials Chemistry C
·
2021
·Vol. 9
·期 7
·2530-2538
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IF 7.393
Yao Tong,Mengfeifei Jin,Ya Chen,Yi Zhao,Haisheng Yang,Qin Wang,Lanlan Zhai,Xiaojuan Liang,Weidong Xiang
Lead halide perovskite CsPbX3 (X = Cl, Br, and I) nanocrystals (NCs) are widely used in the newest generation of lighting display equipment because of their excellent optical properties. However, their poor stability remains an urgent issue to overcome. Encapsulation has become a significant and effective strategy to promote the stability of perovskite NCs, particularly by the package coating of polymer and porous materials. Herein, a simple two-step encapsulation strategy is adopted to fabricate CsPbBrI2@zeolite/PMMA composite films to replace the previous preparation methods of perovskite films. A highly efficient and stable red-emitting material with great colour purity and excellent PLQY of ∼53.9% is manufactured by this simple and effective packaging method. Furthermore, because of the first-encapsulation with zeolite, the CsPbBrI2@zeoite/PMMA composite films not only reduced the agglomeration of NCs but also obtained better optical performance and environmental stability compared to that of pure CsPbBrI2/PMMA. Ultimately, WLEDs constructed by the red-emitting CsPbBrI2@zeolite/PMMA composite material achieve an outstanding colour rendering index, luminous efficiency and correlated color temperature (CRI = 94.5, LE = 77.22 lm W−1 and CCT = 5354 K), and realize tunable colour coordinates of (0.3359–0.32912, 0.3455–0.3336) in the white light area, implying that CsPbBrI2@zeolite/PMMA is very promising for obtaining a high CRI of WLEDs instead of traditional phosphor. The facile two-step encapsulation method proposed in this study provides a prospect for obtaining high-quality perovskites.
研究领域:
材料科学
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光学工程
✓ 已验证
DOI
高影响因子
Applied Materials Today
·
2025
·
IF 6.9
Wasim Ullah Khan,Waheed Ullah Khan,Haiou Zhu
Thermal quenching and brightness are significant challenges for many phosphors, particularly those used in WLEDs, restricting their effectiveness for large-scale implementation. However, developing phosphors with both anti-thermal quenching (anti-TQ) and high brightness remains quite challenging. Here, we report on the synergistic effect (SE) of energy transfer (ET) offset enabling anti-TQ and intrinsic suppression of concentration quenching (CQ) in sensitized photoluminescent schemes. Anti-TQ (102.1%@400 K) is achieved through the synergistic effect of ET and strong structural rigidity. The chromaticity-shifting (ΔEs) level is 8.63×10 −3 , indicating that it retains PL thermal stability comparable to commercial phosphors. The sensitization effects were investigated both experimentally and through theoretical models as a function of Dy 3+ concentrations. The ET process were studied based on the force electric dipole at each ion, achieving an efficiency of 83.4% and ET rates of 165.8%. The Ca 3 ScAl 3 B 4 O 15 :0.015Tm 3+ ,0.12Dy 3+ -based WLED exhibits satisfactory parameters of R a (83.9) and low-CCT (3345 K). The results highlight how emitters play a crucial role in dissipating excitation energies, offering a new avenue for improving the efficiency of sensitized luminescent materials.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 17
·5587-5596
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IF 4
Zhijian Liao,Yan Li,Jiaxing Zuo,Guang Chen,Heng Liang,Shihao Wu,Jiaqing Peng,Xinyu Ye
For high-efficiency lighting and wide color gamut backlight display, high-quality narrow-band red phosphors for WLEDs are still in high demand. Herein, a novel red-emitting fluoride phosphor Cs2NaGaF6:Mn4+ was successfully synthesized by a simple two-step co-precipitation method and exhibits ultra-intense zero-phonon lines (ZPLs) and long wavelength phonon sidebands under 468 nm blue light irradiation. The ZPL emission peak of Cs2NaGaF6:Mn4+ was located at 627 nm, which is much stronger than its υ6 vibration peak, more matchable with the eye-sensitive region of humans, and beneficial for obtaining higher luminous efficiency of WLEDs. Interestingly, the υ6 vibration peak of this red phosphor is at 636.5 nm, which is larger than that of the common fluoride phosphor A2BF6:Mn4+ (usually at about 630 nm, represented by K2SiF6:Mn4+) at about 6.5 nm. Thanks to the longer wavelength of the υ6 vibration peak, the chromaticity coordinates (0.7026, 0.2910) with a larger x-coordinate value were realized, leading to a potentially wider color gamut of WLEDs. In addition, this phosphor has high thermal stability and its emission intensity at 423 K remains 93.7% of the initial intensity at room temperature. The lumen efficiency of WLED1 packaged with a mixture of Cs2NaGaF6:Mn4+ and YAG:Ce3+ on the InGaN blue chip is 115.7 lm W−1 with the color temperature (Tc) = 3390 K and the colour rendering index (Ra) = 92.5 under 20 mA driving current. The chromaticity coordinates of WLED2 packaged with Cs2NaGaF6:Mn4+ and β-SiAlON:Eu2+ on the InGaN blue chip are (0.3149, 0.3262) and the calculated color gamut is up to 118.4% (NTSC). These results indicate that Cs2NaGaF6:Mn4+ red phosphors have promising applications in the high-quality lighting and display fields.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2025
·
IF 3
Guo Wenhang,Zeng Liang,Zhang Xinyuan,Cai Xiaoyu,Su Tan,Su Zhongmin
A silicate inorganic phosphor matrix, CJU-1-Eu (K 3 EuSi 6 O 15 ), based on rice husk-derived biomass silicon, was synthesized via a hydrothermal method. The material was doped with Tb 3+ ions, and the effect of Tb 3+ concentration was investigated, resulting in a series of tunable white-light inorganic phosphors (CJU-1-Eu: x Tb 3+ ) ranging from warm white to cool white. The CJU-1-Eu:0.04Tb 3+ inorganic white-light phosphor was combined with a UV chip to produce the white-light-emitting diode (WLED) device. The device exhibited CIE coordinates of (0.332, 0.327) and the color rendering index (CRI) of 86.5 at 100 mA current. This white-light phosphor achieves both the recycling and high-value utilization of rice husk ash.
研究领域:
材料科学
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环境科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Jiang Guo,Junlan Guo,Jing Gao,Jiexin Chen,Ya Yang,Yue Yang,Lingling Zheng,Yanyan Li,Lei Zhao,Bin Deng,Ruijin Yu
Novel orange-red-emitting LaNb 2 VO 9 (LNV): x Sm 3+ ( x = 0–35 mol%) phosphors were successfully synthesized through the traditional high-temperature solid-state reaction method. The crystal structure, SEM images, particle size distribution , XRD spectra, optimal concentration, zero-thermal-quenching behaviors, and luminescent stability of the samples were exhaustively studied. In particular, the phosphors presented broadband excitation that consisted of O 2− →V 5+ and O 2− →Sm 3+ charge transfer bands (CTB). Under 308 nm excitation, LNV:5 mol%Sm 3+ phosphor emitted orange-red light with high intensity at the wavelength of 598 nm due to the 4 G 5/2 → 6 H 7/2 transition of Sm 3+ ions. The sample with the optimal doping concentration of 5 mol% exhibited zero-thermal-quenching. Furthermore, a white light-emitting diode (WLED) with the Commission Internationale de L'Eclairage (CIE) coordinate of (0.347, 0.348) and the superior color rendering index (CRI, R a ) of 90 was smoothly fabricated. With the LNV: 5 mol%Sm 3+ phosphor, the level 1–3 structure of latent fingerprints (LFPs) and the detailed features of lip prints were clearly detected under ultraviolet irradiation. Ultimately, the phosphor effectively detected LFPs in various daily life circumstances. Consequently, the zero-thermal-quenching orange-red LNV:Sm 3+ phosphors have several promising applications in WLEDs and personal identification.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL PHYSICS
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2024
·
IF 2
Xuan Gu,Zheng He,Xao-Yu Sun
Eu 2+ -doped Sr 2 LaGaO 5 phosphors were prepared using a high-temperature solid-state route in a furnace at 1450 °C. Their phase, microstructure, and luminescent performance were thoroughly investigated. The XRD measurements indicate that the prepared phosphors exhibit a tetragonal phase. Upon excitation at 450 nm, the Sr 2 LaGaO 5 :Eu 2+ phosphors demonstrate a broad red emission ranging from 475 to 850 nm, with a peak at 620 nm. At a doping concentration of 6 %mol Eu 2+ , the phosphors exhibit the highest emission intensity, characterized by CIE coordinates of (0.536, 0.453) and a color purity of 65.53 %. The temperature-dependent emission analysis reveals that the phosphors possess excellent thermal stability. The emission intensity of the Sr 2 LaGaO 5 :0.06Eu 2+ phosphor at 420 K is about 53.9 % of the initial intensity measured at 300 K, with a thermal activation energy of 0.393 eV. The pc-WLED device was constructed via the combination of an LED chip, yellow Y 3 Al 5 O 12 :Ce 3+ and the prepared Sr 2 LaGaO 5 :Eu 2+ phosphors, resulting in the emission of warm white light with a CCT value of 4985 K.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2022
·
IF 4.632
Pan Liang,Lianqing Li,Tong Shen,Wenli Lian,Zhihong Liu
In this work, through a facile method of low-temperature (only 350 °C) self-reduction, 1D nano-sized M 2 B 5 O 9 Cl:Eu 2+ (M = Sr, Ca) blue phosphors with highly efficient performance can be obtained. The crystal structure, morphology and photoluminescence (PL) properties including thermal stability of M 2 B 5 O 9 Cl:Eu 2+ (M = Sr, Ca) phosphors were investigated. The M 2 B 5 O 9 Cl:Eu 2+ (M = Sr, Ca) phosphors show broad band excitation spectra and narrow band emission spectra . The photoluminescence quantum yields (PLQY) of M 2 B 5 O 9 Cl:Eu 2+ (M = Sr, Ca) are as high as 98% and 87.2%, respectively. Furthermore, the color purities of M 2 B 5 O 9 Cl:Eu 2+ (M = Sr, Ca) can reach 99.1% and 93.2%, respectively. When heated up to 150 °C, the emission intensities of M 2 B 5 O 9 Cl:Eu 2+ (M = Sr, Ca) phosphors can still keep 72.7% and 80.0%, respectively. Finally, the above-mentioned phosphors exhibit outstanding performance when manufacturing WLEDs.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Electronic Materials
·
2020
·
IF 0
Fei Tang,Haoqi Li,Kangzhen Tian,Shijie Xu,Xiaojun Wang,Chenhui Xie,Honggang Ye,Yongge Cao
Hunting for a type of green phosphor with outstanding properties is of much significance for improving the performance of display backlights. In this work, a series of efficient Eu2+-activated RbLi7Si2O8 (denoted as RLSO:Eu2+) green phosphors with different doping concentrations were prepared via a low-temperature solid-state reaction approach under a reduced atmosphere. Photoluminescence (PL) measurements show that the prepared green phosphor with 8 atom % doping concentration of Eu exhibits the best internal quantum yield (IQY) of 95.8%. Besides, the phosphor delivers a good anti-thermal quenching behavior at temperatures <200 K, that is, there is no significant drop in luminescence intensity. Such thermal behavior is well consistent with the temperature dependence of measured luminescence lifetimes. The spectral analysis of the low-temperature luminescence spectrum with a semiclassical time-dependent approach reveals that three electronic levels of the Eu2+ ion coupled with a common low-frequency vibrational phonon mode with an energy of 21 meV shall be responsible for the high-efficiency luminescence of the prepared phosphor. Using the as-prepared green phosphor and K2SiF6:Mn4+ red phosphor, a white light-emitting diode (LED) device with high luminous efficacy (111.08 lm/W) and wide color gamut (112% NTSC) is fabricated on an InGaN blue chip.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
Journal of Materials Chemistry C
·
2019
·Vol. 7
·期 30
·9203-9210
·
IF 6.641
Y. Y. Zhou,E. H. Song,M. G. Brik,Y. J. Wang,T. Hu,Z. G. Xia,Q. Y. Zhang
Mn4+-doped fluoride red-emitting phosphors have been developed for backlighting white light-emitting diodes (WLEDs). However, the long fluorescence lifetime (τ > 5 ms) leads to the image-retention phenomenon for the human eye when Mn4+ is doped into equivalent X sites in A2XF6 (A = Na, K, Rb, Cs; X = Si, Ge, Ti, Zr). Herein, we report on novel red-emitting A2NaScF6:Mn4+ (A = K, Rb, Cs) (ANSF) phosphors with short fluorescence lifetimes (τ < 4 ms) and characteristic zero phonon line (ZPL) emission, which can be realized via non-equivalent doping of Mn4+ into Sc3+ sites. Density functional theory (DFT) calculations verified the formation of a slightly distorted environment of Mn4+ and an Na+ vacancy to balance the charge with Mn4+ non-equivalent doping. The WLED backlight using ANSF as a red-light component can reach a wide color gamut above 105% of the National Television Standards Committee (NTSC) standard, and the image-retention on the backlighted screen can be effectively avoided compared to the backlight obtained using commercial K2SiF6:Mn4+. Such a Mn4+ non-equivalent doping strategy opens a new perspective for the modification of local symmetry and enhancement of the luminescence properties of Mn4+-doped red-emitting fluoride phosphors.
研究领域:
材料科学
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光学工程
✓ 已验证
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Zenan Zhang,Haotian Gu,Tenglong Sun,Yongfeng Liu,Muzhi Cai,Junjie Si,Gongxun Bai,Laurent Calvez,Shiqing Xu
Poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) has emerged as a promising candidate for high-cost transparent conductive oxide (TCO) electrodes. However, achieving high conductivity in PEDOT:PSS typically requires treatment with strong acids, which presents inherent risks. In this study, we propose an alternative approach utilizing a mild methane sulfonic acid (MSA) treatment for PEDOT:PSS as a transparent conductive electrode (TCE). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses unveil heightened phase separation between PEDOT and PSS by MSA treatment, accompanied by structural modifications in PEDOT. Moreover, the interfacial morphology between the MSA-treated electrode and the hole injection layer underwent significant changes. It is precisely this improved interface morphology, combined with enhanced conductivity, that significantly improves the efficiency of the obtained TCO-free blue quantum dot light-emitting diode (QLED) by 300 % compared to the reference device. Finally, leveraging the high performance of the TCO-free blue QLEDs, we fabricate the above device on a yellow-emissive phosphors-in-glass substrate, enabling a white light-emitting LED (WLED) device. This experiment not only elucidates the structural changes in PEDOT:PSS under mild acid treatment but also introduces an innovative strategy for developing high-performance PEDOT:PSS electrodes.
研究领域:
材料科学
·
光电工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Xinyi Zhang,Wenqi Xia,Zehua Xue,Wanyu Zhao,Xiyuan Zhang,Zuobin Tang
Broadband yellow-green-emitting materials help to improve the color rendition performance of phosphor-converted white light-emitting diodes (pc-WLEDs). Herein, we report a Bi 3+ -activated double perovskite (La 2 MgHfO 6 ) broadband yellow-green-emitting phosphor synthesized via high-temperature solid-state reaction. Structural characterization confirms phase-pure crystallization in the P21/n space group, while spectral analysis reveals a broad yellow-green emission (λ em = 544 nm, FWHM = 137 nm) under 370 nm excitation, attributed to the parity-allowed 3 P 1 → 1 S 0 transition of Bi 3+ in [LaO 8 ] dodecahedron and [Mg/HfO 6 ] octahedra. The material effectively suppresses concentration quenching owing to the relatively large interionic distances within its crystal structure. Meanwhile, its emission peak exhibits a red-shifting (Δλ = 30 nm) with varying excitation wavelengths, which stems from the distinct responses of different luminescent centers to excitation energy. Additionally, it demonstrates good thermal stability, with minimal temperature-induced changes in peak position and full width at half maximum (FWHM). When combined with commercial red (CaAlSiN 3 :Eu 2+ ) and blue (BAM:Eu 2+ ) phosphors, the fabricated WLED exhibits bright white light with superior color rendering (Ra = 86.9) and comfortable correlated color temperature (CCT = 4994 K). The yellow-green emission significantly enhances spectral continuity, demonstrating great potential as a rare-earth-free component for high-quality full-spectrum lighting systems.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Zhigang Yang,Shuqin Zhang,Junshuai Chen,Tianqing Sheng,Xinran Lv,Xuguang Wei,Guoqiang Qin,Gang Yu
Owing to inherent structural instability of perovskite quantum dots, they are instability in humid environments and high temperatures conditions. To address this issue, a simple, environmentally friendly glass encapsulated technology is used to protect the perovskite quantum dots. Meanwhile, the dual-phase perovskite structure realized by phase transition engineering can further increase the stability of perovskite quantum dots. In this study, 3D CsPbBr 3 /0D Cs 4 PbBr 6 dual-phase coexisting perovskite quantum dot glass powders were synthesized through melt quenching and subsequent crystallization induction of thermal treatment and water molecule, respectively. Results showed that compared with thermal treatment induction, perovskite QDs glass powders by water molecules induction exhibited a high PLQY of 24.7 % with a central wavelength of 519 nm and displayed excellent environmental stability. By combining green fluorescence from 3D CsPbBr 3 /0D Cs 4 PbBr 6 QDs glass powders and red fluorescence powders (CaAlSiN 3 :Eu), a WLED device with an impressive EQE of 20.6 % was created, indicating a promising application potential.
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）