CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Shuai Zhang,Yifei Zhao,Jiadong Zhou,Hong Ming,Chun-Hai Wang,Xiping Jing,Shi Ye,Qinyuan Zhang
Manganese (II) compounds are promising luminescent candidates for white light-emitting diodes (WLEDs) applications. However, the forbidden d - d transition of Mn 2+ ion makes the absorption of blue light and emission relatively weak without a sensitizer. The strategy of isolating MnX n (X is the ligand) with some ionic liquids is used to design two new hybrid compounds in this study, focusing on the orbital hybridization to relax the parity selection rule of the d - d transition. A large hindrance of the organic cations in the two new Manganese (II) hybrids enables a large Mn-Mn distance (up to ~ 10 Å) to form zero-dimensional (0D) structures, and the Mn sites in both compounds have a low site symmetry ( C 2 or C 1 ). The 0D structure of MnX n polyhedral is beneficial to isolatedly investigate the orbital hybridization of the ligand and Mn 2+ ion. A higher orbital hybridization extent for Mn-Br bond is evidenced by Density Functional Theory (DFT) simulation. This conclusion leads to the strong and stable green light emissions under preferable blue light (460 nm) excitations, giving photoluminescence quantum yields (PLQYs) as high as 76%. The WLEDs fabricated with these compounds have presented high luminous efficiency up to ~130 lm/W and survived multiple stability tests. The research favors the discovery of ideal Mn compounds for displays and lighting applications.
研究领域:
材料科学
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光电
·
光子学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2021
·Vol. 50
·期 46
·17281-17289
·
IF 4.39
Dayu Huang,Yue Liu,Qiuyun Ouyang,Hongzhou Lian,Jun Lin
The stability of perovskite quantum dots (PQDs) plays a vital role in practical devices. Besides silica coating, embedding PQDs in zeolites is another strategy to improve their stability significantly. Although the zeolite rigid framework has been reported to protect PQDs, there are few reports on the in situ synthesis of PQDs in zeolites. In this work, cubic phase CsPbX3 (X = Br, I) nanocrystals were successfully prepared by the ion exchange method combined with a non-polar organic trigger. Dropping a certain amount of ZnM2 (M = Br, I) solution into the intermediate product Cs4PbCl6 nanocrystals resulted in the formation of the final CsPbX3 nanocrystals. The ZnM2 solutions were prepared in non-polar solvents (hexane, octane, or chloroform). The highest photoluminescence quantum yield (PLQY) of the synthesized CsPbX3@zeolite composites can reach 83%, with a lifetime of 1.37 μs. The stability of the CsPbX3@zeolite composites thin film against damage from air and light is significantly improved. We fabricated white light-emitting diodes (WLEDs) using CsPbBr3@zeolite as the green light source and CsPbI3@zeolite as the red light source to further emphasize the practical application effect of the CsPbX3@zeolite composites. This work not only provides a new method for the synthesis of CsPbX3 nanocrystals but also involves the in situ synthesis of high stability CsPbX3@zeolite composites within the zeolite.
研究领域:
材料科学
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光电技术
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纳米技术
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光伏技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Advanced Optical Materials
·
2022
·Vol. 10
·期 16
·2200217
·
IF 10.05
Chuying Wang,Ya-Kun Wang,Ziliang Li,Jingwei Luo,Randy Sabatini,Tao Zhang,Edward H. Sargent,Zhengtao Deng
Recently, metal halide perovskites have attracted considerable interest as highly emissive phosphors for use in white light-emitting diodes (WLEDs). In perovskites, the migration of halide anions between green-emitting bromide (e.g., CsPbBr 3 ) and red-emitting iodide (e.g., CsPbI 3 ) materials is one obstacle to application. Here perovskite WLEDs that do not suffer from the anion exchange problem are reported: this is done by developing green-emitting single-layer sheets of (RNH 3 ) 2 PbI 4 (R = C 18 H 35 –, C 12 H 25 –, and C 8 H 17 –) and uniting these with red-emitting CsPbI 3 perovskite quantum dots (QDs). It relies on self-assembly from ligand-capped CsPbI 3 nanocrystals to form single-layer sheets of (C 18 H 35 NH 3 ) 2 PbI 4 : via judicious selection of alkylamines and alkyl acids, (RNH 3 ) 2 PbI 4 single-layer sheets that exhibit bright and stable green emission with well-defined single-layer thickness are produced. Emission from 505, 512 to 536 nm is tuned and a narrow (<20 nm) linewidth is retained. Perovskite LEDs that produce white light with chromaticity coordinates (0.32, 0.33) and color gamut that reaches 117% National Television System Committee (NTSC) in the International Commission on Illumination (CIE) 1931 color space are demonstrated.
研究领域:
材料科学
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光电技术
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光子学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2025
·
IF 5.4
Zhihao Jiang,Zihao Han,Jianwei Dao,Tiqun Wei,Zhenglin Jiang,Liang Yang
Narrowband red-emitting phosphors excited by near-ultraviolet (near-UV) light can significantly improve the R 9 and are promising for white light-emitting diodes (WLEDs). In this work, Li 6 Y 1-x (BO 3 ) 3 :xEu 3+ is first reported as a novel narrowband red phosphor, which exhibits a high R 9 value (83.8) under near-UV chip excitation for fabricating WLEDs with high color rendering index (CRI). X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) confirmed that Eu 3+ successfully partially substituted Y 3+ in the Li 6 Y(BO 3 ) 3 lattice, and all samples maintained a monoclinic P 2 1 /c structure without impurity phases. Under 396 nm near-UV excitation, Li 6 Y 1-x (BO 3 ) 3 :xEu 3+ phosphors showed intense red emission at 616 nm (attributed to the Eu 3+ 5 D 0 → 7 F 2 transition) with a full width at half maximum (FWHM = 4.8 nm), and this narrowband feature directly contributes to the improved R 9 . The optimum Eu 3+ doping concentration was 0.07; at this concentration, the red-orange ratio (the intensity ratio of 5 D 0 → 7 F 2 to 5 D 0 → 7 F 1 transitions) reached a maximum value of 4.46, indicating Eu 3+ is in a low-symmetry crystal field with high red emission purity. The luminescent intensity at 423 K remained 68.9 % of that at room temperature, with an activation energy of 0.186 eV, demonstrating excellent high-temperature stability. When the optimal phosphor was mixed with commercial BaMgAl 10 O 17 :Eu 2+ blue and (Ba, Sr) 2 SiO 4 :Eu 2+ green phosphors and packaged on a 395–400 nm chip, the fabricated WLED exhibited a high CRI (R a = 87) and a suitable correlated color temperature (CCT = 5753 K). The results demonstrate that Li 6 Y(BO 3 ) 3 :Eu 3+ is a very promising red phosphor candidate for high-CRI solid-state lighting
研究领域:
材料科学
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光学材料
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固态照明
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光子学
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发光材料
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2018
·Vol. 47
·期 16
·5614-5621
·
IF 4.099
Luqing Xi,Yuexiao Pan,Shaoming Huang,Hongzhou Lian,Jun Lin
Herein, a novel red phosphor based on seven-coordinated Mn4+ ion-doped tridecafluorodizirconate, Na5Zr2F13 (NZF), has been synthesized by stirring a mixture of K2MnF6, NaF, and H2ZrF6 at room temperature. The crystal structure and morphology of the as-obtained phosphor NZF:Mn have been determined by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The composition and distribution of Mn4+ ions in NZF have been confirmed by energy-dispersive spectroscopy (EDS) and element mapping via transmission electron microscopy (TEM). The phosphor NZF:Mn exhibits a strong zero phonon line (ZPL) at 616 nm under excitation of blue light from a GaN light-emitting diode (LED) chip; this is attributed to the low symmetry of Mn4+ ions occupied in a seven-coordinated environment. The luminescence intensity of NZF:Mn has been optimized by controlling the synthesis procedure and synthetic parameters. The luminescence mechanism of the red phosphor NZF:Mn has been investigated according to the detailed experimental results. A warm white light has been produced by a WLED fabricated with the red phosphor NZF:Mn and the commercial yellow phosphor Y3Al5O12:Ce3+ (YAG:Ce) on a GaN LED chip.
研究领域:
材料科学
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无机化学
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发光材料
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固态照明
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晶体化学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Wanyin Ge,Maohao Yang,Honglei Yin,Shifan Shang,Zili Luo,Xin Xie,Ye Tian
SiAlON-based phosphors have garnered considerable attention in the field of white lighting owing to their excellent thermal stability, and rare earth doped SiAlON-based phosphors are expected to be used in a new generation of lighting sources. In this work, Eu 2+ or Ce 3+ doped Si 3 Al 3 O 3 N 5 phosphors were synthesized by high temperature solid phase method. The microstructure of the phosphors exhibited irregular grain. The two phosphors exhibit green and cyan luminescence under 365 nm excitation, which are derived from the 5 d -4 f transitions of Eu 2+ and Ce 3+ , respectively. The quenching concentrations are 3 % and 4 % for Eu 2+ and Ce 3+ doped phosphors , respectively. The fluorescence intensity of Eu 2+ and Ce 3+ activated SiAlON powders decreased to 50 % of the room temperature intensity at 179 °C and 170 °C, respectively. The thermal activation energy values of the two phosphors were 0.35 eV, and the coordinate configuration diagram was constructed to comprehensively analyze the thermal quenching behavior of phosphors. Finally, the two phosphors powders were mixed with red and blue fluorophore to obtain white LEDs, showing low color temperature, high color rendering, high power unsaturation and long half-life. The SiAlON-based phosphors with excellent thermal stability obtained in this work achieve different wavelengths of luminescence in the green region. The results show that the β -Si 3 Al 3 O 3 N 5 phosphor can be used as a candidate material for high-quality green light supplement for wLEDs .
研究领域:
材料科学
·
光电子学
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发光材料
·
固态照明
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2020
·
IF 4.65
Ying Liu,Bingfeng Shi,Qian Liu,Changli Lü
All-inorganic perovskite quantum dots (PQDs) have received great attention in the field of optoelectronics because of their excellent optical properties . However, the application of perovskite is always limited because of its poor stability. Herein, the CsPbBr 3 PQDs were stabilized by two-dimensional (2D) nanosheets of layered double hydroxide (LDH) for the first time using a simple one-pot in-situ growth route. In the as-synthesized LDH/CsPbBr 3 nanocomposite, CsPbBr 3 PQDs are uniformly attached to the surface of the LDH nanosheets . The resulted composite powder showed good green-luminescence, high solid PLQY (∼41%), narrower FWHM (∼20.0 nm), long fluorescence lifetime, excellent humidity stability and photostability. The unique 2D structured LDH nanosheets imparts significantly enhanced stability to LDH/CsPbBr 3 composite. All these advantageous properties make the LDH-based fluorescent composite good candidate for flat-panel displays and lighting devices. Our research proposes a novel method to stabilize PQDs by using inorganic 2D nanosheet materials and provides new opportunities for the applications of perovskite in optoelectronic field such as white light-emitting diode (LED).
研究领域:
材料科学
·
纳米技术
·
光电子学
·
钙钛矿量子点
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固态照明
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Weijie Yuan,Dongwen Cai,Shuai Ma,Huaiyong Li,Quansheng Wu,Xufeng Zhou,Wanying Geng
This article systematically investigates the preparation, structure, and luminescent properties of a novel Eu 3+ -based germanate phosphor: NaInGe 2 O 6 (NIGO): Eu 3+ . NIGO: Eu 3+ exhibits strong absorption in the near ultraviolet (NUV) and blue region, which enables it to be effectively excited by the blue LED chip. Under 465 nm excitation, NIGO: Eu 3+ exhibits a red emission peak at 610 nm, reaching 82.60 % and 68.6 % of the emission intensity of Y 3 Al 5 O 12 (YAG): Ce 3+ and K 2 TiF 6 :Mn 4+ . NIGO: Eu 3+ also has good thermal stability, retaining 76.23 % even at 150 °C. Furthermore, combining NIGO: Eu 3+ with commercial YAG: Ce 3+ phosphors significantly enhances the luminescent performance of blue-chip-excited white light-emitting diodes (WLEDs), including improvements in color rendering index (CRI) and correlated color temperature (CCT). This work indicates that NIGO: Eu 3+ phosphors possess promising potential for WLED applications.
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Dan Zhang,Taifang Zhang,Jingxi Li,Bibo Lou,Peng Wang,Chonggeng Ma
Currently, the development of innovative, efficient phosphors featuring near-ultraviolet excitation and broadband emission, notably Bi 3+ -activated phosphor, is pivotal for realizing high-performance white light-emitting diodes (WLEDs). In this work, we report a series of broadband orange-green emitting YBaZn 3- y Mg y GaO 7 : Bi 3+ phosphors with strong n-UV excitation. By employing cationic substitution, we successfully tuned the emission wavelength from 605 to 550 nm, thereby unlocking potential for multifunctional applications in solid state lighting and information encryption. YBaZn 3 GaO 7 : 0.015Bi 3+ phosphor generates 605 nm orange emission with a full width at half-maximum (FWHM) of 220 nm under 330 nm n-UV excitation, with high luminescence intensity and excellent thermal stability. In addition, the luminescence mechanism of Bi 3+ ions in YBaZn 3- y Mg y GaO 7 : Bi 3+ was investigated thoroughly. A high-performance W-LED device has been fabricated, utilizing a unique YBaZn 3 GaO 7 : 0.015Bi 3+ phosphor and commercial blue and green phosphors, pumped by a 365 nm chip. This phosphor-converted (pc) WLED has an excellent color-rendering index (R a ) of 95.6 and a comfortable correlated color temperature (CCT) of 5193 K. This result indicates its potential applications in the field of health lighting. Furthermore, the orange-green YBaZn 3- y Mg y GaO 7 : Bi 3+ phosphor demonstrates precise information identification in information encryption, confirming its potential in this field.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Xiaoshuang Li,Chengjue Guo,Hongwei Wang,Yeqing Chen,Jiangcong Zhou,Jun Lin,Qingguang Zeng
By hetero-valence substituting Ba 2+ -Si 4+ for Lu 3+ -Al 3+ pair in Lu 3 Al 5 O 12 : Ce 3+ , a new green phosphor Ba 1.5 Lu 1.5 Al 3.5 Si 1.5 O 12 : Ce 3+ (BLAS: Ce 3+ ) has been obtained. It crystallizes in garnet structure with space group Ia -3 d (230). In the structure, Ba 2+ ions are incorporated into both dodecahedral Lu 3+ and octahedral Al 3+ sites while Si 4+ ions only occupy tetrahedral Al 3+ sites. Under the blue light irradiation of 450 nm, an intense green light peaking at 520 nm was observed and the PL spectrum can be fitted in two Gaussian components, due to the crystal field splitting of Ce 3+ 5 d states under D 2 symmetry constrains. The optical doping concentration of BLAS: Ce 3+ is 6% mol, of which the IQE and EQE are 89.1% and 51.8%, respectively. Furthermore, this sample exhibits an extremely good thermal stability, i.e. the integrated emission intensity is still more than 90% of the initial intensity at 480 K. Then, a w-LED device was fabricated from this new green phosphor BLAS: Ce 3+ and commercial red phosphor (Ca,Sr)AlSiN 3 : Eu 2+ , which shows a quite high color rendering (Ra = 88.2) and a relatively low color temperature 4772 K. Besides, the phosphor exhibits a stable chromaticity under different acceleration voltages. The phosphor may be promising material for the development of solid-state lighting and display systems.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2021
·
IF 5.165
Guixian Li,Xingyang Shi,Xinyue Lu,Qinan Mao,Lang Pei,Yiwen Zhu,Meijiao Liu,Liang Chu,Jiasong Zhong
Modulating the crystal field environment around the emitting ions is an effective strategy to improve the luminescence performance of the practical effective phosphor materials. Here, smaller Y3+ ions are introduced into substituting the Gd3+ sites in Ba2GdNbO6:Mn4+ phosphor to modify the optical properties, including the enhanced luminescence intensity, redshift, and longer lifetime of the Mn4+ ions. The substitution of smaller Y3+ ions leads to lattice contraction and then strengthens pressure on the local structure, enhances lattice rigidity, and suppresses nonradiative transition. Moreover, the prototype phosphor-converted light-emitting diode (LED) demonstrates a continuous change photoelectric performance with a correlated color temperature of 4883–7876 K and a color rendering index of 64.1–83.2, suggesting that it can be one of the most prospective fluorescent materials applied as a warm red component for white LEDss. Thus, the smaller ion partial substitution can provide a concise approach to modulate the crystal field environment around the emitting ions for excellent luminescence properties of phosphors toward the modern artificial light.
研究领域:
材料科学
·
光学材料
·
固态照明
·
荧光粉化学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2020
·
IF 3.306
Yongsheng Yang,Zhiduo Liu,Da Chen,Bingli Gu,Bo Gao,Zihao Wang,Qinglei Guo,Gang Wang
In this work, nitrogen-doped graphene quantum dots (N-GQDs) with high blue fluorescence are synthesized by the one-pot hydrothermal method from benzimidazoles. The as-fabricated N-GQDs possess a homogeneous size of 3.8 nm, good crystallinity, pip photostability, good water soluble, and a high quantum yield of about 25 %. In addition, it is found that the fluorescence of N-GQDs can be obviously quenched by tetracycline (TC) and elevated temperature. The detection of TC is implemented, with a detection limit of 0.21 μmol L −1 . For the temperature sensing, the fluorescence intensity shows a linear reduction between 25 °C and 100 °C. Moreover, reversible and stable abilities of temperature sensing are demonstrated. Owing to the superior optoelectronic properties, white light emitting diodes (WLEDs) using the N-GQDs as the phosphor are fabricated, and the CIE coordinates is (0.357, 0.315) with the color temperature of 4427 K. The results reported here will expand the multiple applications of N-GQDs in environment monitoring, biosensing engineering and optoelectronic devices.
研究领域:
材料科学
·
环境监测
·
生物传感
·
光电设备
✓ 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）