CERAMICS INTERNATIONAL
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2024
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IF 5.1
Shengqian Wang,Junqiang Gu,Jinying Liu,Feiyan Xie,Chaochao Tao,Shuo Wang,Hualan Xu,Shengliang Zhong
Phosphors with high luminescence efficiency, tunable emission and high color rendering index (CRI) are vital importance for the quality of white light emitting diodes (w-LEDs) in real application. In this work, a new single phase color-tunable Na 5 Lu(WO 4 ) 4 :Tb 3+ ,Eu 3+ phosphor with outstanding luminescent properties was designed and synthesized. Its crystal structure, electronic structure, and luminescence features were studied in detail. The band gap of the host was calculated to be about 4.68 eV. The differential charge distribution after Tb, Eu doping through density functional theory simulation theoretically proved the electron redistribution in the W-O bond upon substitution of Tb 3+ /Eu 3+ . The energy transfer of Tb 3+ →Eu 3+ enabled tunable emission of luminescent colors from green to orange-red due to the quadrupole-quadrupole interaction. The optimal Na 5 Lu(WO 4 ) 4 :60%Tb 3+ ,20%Eu 3+ phosphor exhibited excellent photoluminescence quantum yield of 84.19 % and good luminescent thermal stability (I 423K/298K = 75.90%) with an activation energy of 0.1976 eV. Finally, a white LED device with color coordinates of (0.3371, 0.3636), color rendering index of 89.4 and correlated color temperature of 5334 K was fabricated. These findings demonstrated that Na 5 Lu(WO 4 ) 4 :60%Tb 3+ ,20%Eu 3+ phosphor could be a potential orange-red-emitting color converter for white LEDs. This work not only assisted in the understanding of experimental observations but also provided a theoretical basis for the rational design of phosphors.
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
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Zhiwei Xia,Yuhan Wang,Rujun Yang,Mengdi Xu,Cunjian Lin,Zhongyuan Li,Ying Lv,Xiaopeng Chi,Shihai You
The interstitial site engineering that purposely creates interstitial luminescent centers in suitable hosts has become an intriguing strategy in designing novel inorganic phosphors. However, effectively tuning the photoluminescence of interstitial activators remains tough challenging at this stage. Here, we demonstrate the effective modulation of interstitial luminescence in inorganic phosphor. In detail, the blue emission band ( λ em = 446 nm) of interstitial Eu 2+ doped α -cristobalite (SiO 2 :Eu 2+ ) is largely enhanced and broadened via a partial, aliovalent substitution of Si 4+ by Al 3+ . After introducing Al 3+ ions into SiO 2 lattice, the full width at half maximum of the blue emission band increase from 59 to 76 nm with a triple growth in quantum efficiency (10.82% → 35.56%). Moreover, the thermal stability improves significantly with a high emission retention of 60% at 325 °C (SiO 2 :0.06Al 3+ ,0.005Eu 2+ ), far higher than that of the parent SiO 2 :0.005Eu 2+ (30%). Encapsulating blue-emitting SiO 2 :Al 3+ ,Eu 2+ along with two commercial green and red phosphors on an ultraviolet LED chip ( λ em = 375 nm), a white LED device with high color rendering index (Ra > 90) was successful fabricated, showing the great potential of this phosphor for achieving high-quality white LED lighting. This study not only provides a promising bule emitter but also sheds light on modulating interstitial luminescence properties in inorganic phosphors.
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
JOURNAL OF ALLOYS AND COMPOUNDS
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2020
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IF 4.65
Shuang Shu,Yu Wang,Yuee Ke,Bin Deng,Rixin Liu,Qinyang Song,Jianxu Wang,Ruijin Yu
Novel orange-red-emitting tantalate NaCaTiTaO 6 (NCTT): x Sm 3+ ( x = 0.005–0.25) phosphors are synthesized via a solid-state reaction technique at 1300 °C. The phosphors exhibit an orthorhombic perovskite structure with a space group of Pnma (No. 62). At 407 nm excitation, the phosphors show the strongest emission peak at 647 nm belonging to the 4 G 5/2 → 6 H 9/2 transition. The optimal Sm 3+ concentration is 0.05 mol, and concentration quenching is caused by dipole–dipole interaction. The NCTT:0.05Sm 3+ phosphor exhibit a broad bandgap of 3.44 eV and a high color purity of 99.9%. At 420 K, the decrease in intensity is only 10% of the initial value at 300 K for NCTT:0.05Sm 3+ phosphor but 15% for Y 3 Al 5 O 12 :Ce 3+ phosphor. Consequently, the fabricated white light-emitting diodes exhibit a high rendering index value of 89, a good correlated color temperature of 5257 K, and CIE coordinates of (0.339, 0.364). Hence, the Sm 3+ -doped orange-red-emitting NCTT phosphors have potential applications for w-LEDs.
研究领域:
材料科学
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光学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
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2025
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IF 4.7
Yichen Zhu,Yubin Kang,Jing Su,Zhi Wen,Mingchun Li,Qiangqiang Zhu,Yue Zhai,Juan Kang,Yanghui Li,Le Wang
Lead halide perovskites have garnered interest in light-emitting diode (LED) applications due to their strong emission and tunable properties. However, conventional synthesis methods involve energy-intensive thermal processes and hazardous organic solvents, raising environmental concerns. In this study, we report a simple and eco-friendly mechanochemical approach that produces phase-pure blue-emitting Cs3Cu2I5 (emission at 440 nm) and yellow-emitting CsCu2I3 (emission at 570 nm) phosphors through polarity modulation and control of grinding duration. Our comprehensive analysis of the phase transitions during mechanochemical synthesis reveals that pure Cs3Cu2I5 was synthesized from a 3:2 precursor molar ratio in ethanol for 30 min, while pure CsCu2I3 was obtained from a 1:2 precursor molar ratio in an aqueous solution for 7.5 min. Moreover, Raman spectroscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy analyses confirmed that phase-pure phosphors were achieved through these methods. Finally, we fabricated a series of color-adjustable LEDs by mixing Cs3Cu2I5 and CsCu2I3 phosphors in different proportions. This demonstrates the potential of our mechanochemical synthesis for the efficient, large-scale production of next-generation lighting materials with tunable emission.
研究领域:
材料科学
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光学工程
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2025
·
IF 4.2
Rouziaji Alimu,Reziwanguli Yantake,He Jiuyang,Wang Qingling,Aierken Sidike
To achieve high-color-rendering WLED devices, exploration of blue‒cyan phosphors that can be excited by near-ultraviolet (NUV) chips is particularly important to compensate for the cyan gap. In this work, feldspar-structured Sr 1-y Al 2- x Ga x Si 2 O 8 :yCe 3+ blue-cyan phosphors were prepared via a high-temperature solid-phase method and a cation substitution strategy. The luminescence performance of the Sr 0.96 Al 2 Si 2 O 8 :0.04Ce 3+ sample was improved by applying the cation substitution strategy of partially replacing Al 3+ with Ga 3+ , and the representative sample Sr 0.96 Al 1.4 Ga 0.6 Si 2 O 8 :0.04Ce 3+ was obtained. The luminescence intensity increased threefold for the Sr 0.96 Al 1.4 Ga 0.6 Si 2 O 8 :0.04Ce 3+ compound compared to Sr 0.96 Al 2 Si 2 O 8 :0.04Ce 3+ , and a broadband blue‒cyan phosphor with a half-height width of 100 nm was obtained. The representative sample Sr 0.96 Al 1.4 Ga 0.6 Si 2 O 8 :0.04Ce 3+ showed relatively good thermal stability. Sr 0.96 Al 1.4 Ga 0.6 Si 2 O 8 :0.04Ce 3+ was combined with 365 nm NUV LED chips and commercial (Sr, Ca)AlSiN 3 :Eu 2+ to obtain WLED devices with color rendering index (Ra) as high as 94.8 and correlated color temperatures (CCTs) as high as 4831.4 K. These results show that the blue-cyan phosphor complements the cyan component while simplifying the manufacturing process of WLEDs.
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
ACS Applied Electronic Materials
·
2025
·
IF 4.7
Zhixian Wu,Xueyong Zheng,Chunli Jiang,Junhan Xie,Weimin Liu,Bo Li,Hechun Lin,Hui Peng,Chunhua Luo
Tin (Sn)-based perovskite light-emitting diodes (PeLEDs) have garnered significant attention owing to their superior optoelectronic properties, affordable solution processing, and environmental friendliness. However, the properties of Sn-PeLEDs trail those of their lead (Pb) counterparts. The main obstacle is the easy oxidation of Sn2+ to Sn4+ as well as fast crystallization, leading to poor film quality with many defects. Herein, a convenient and effective interface engineering strategy is reported to fabricate (2-thiopheneethylamine)2SnI4 (TEA2SnI4) PeLEDs by introducing different peptides into the PEDOT:PSS hole-transport layer (HTL). Benefiting from the interaction between the peptide molecules and the Sn-perovskite nuclei, the crystallization dynamics are effectively adjusted, leading to an improved film morphology. At the same time, the multiple functional groups of peptides can suppress Sn2+ oxidation and passivate interface defects. Therefore, perovskite films with improved luminescence efficiency are obtained. The perovskite films are further used for the fabrication of pure red PeLEDs with enhanced performance. In particular, the optimized devices based on Leu-Gly-Gly (LGG) achieve a peak external quantum efficiency of 0.5% and a brightness of 136 cd m–2, which are about 2 and 3 times larger, respectively, than those of the reference device. This research offers a general strategy to improve the performance of Sn-PeLEDs via peptide interface engineering.
研究领域:
材料科学
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光学工程
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生物化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
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2024
·
IF 4.3
Yiying Zhu,Guoxun Sun,Yining Wang,Yixin Sun,Xiaole Xing,Mengmeng Shang
Doping lanthanide ions is an efficient method to modify the optical properties of lead-free double-perovskite halides. However, most lanthanide-doped double perovskites show a low luminescence efficiency and require a high excitation energy. Here, we have successfully prepared a series of Ho3+-doped Cs2NaBiCl6 microcrystals through a simple hydrothermal method and obtained strong characteristic emissions of Ho3+ at 492 and 657 nm under low-energy excitation (449 nm). After codoping Mn2+, apart from the characteristic emissions from Ho3+ under 450 nm wavelength excitation, the orangish-red luminescence consisting of the emission band centered at 591 nm from Mn2+ and a sharp emission peak at 657 nm from Ho3+ is obtained under 355 nm UV light excitation. Photoluminescence (PL) emission and excitation spectra, along with the PL decay curves, confirm the existence of an energy-transfer channel from Cs2NaBiCl6 to Mn2+ and then from Mn2+ to Ho3+. The enhanced absorption efficiency (10.5 → 70.7%) suggests that the codoping of Mn2+ overcomes the low absorption efficiency caused by f–f forbidden transitions of Ho3+. Finally, the diverse luminescent performance within the Cs2NaBiCl6:Ho3+, Mn2+ phosphor is realized by altering the excitation wavelength, thereby enabling its application in warm-white-light-emitting diodes and plant growth in this work.
研究领域:
材料科学
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光学工程
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农业科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2024
·
IF 3.9
Lihan Deng,Jin Li,Jiachen Chen,Jin He
Nanoporous Al 2 O 3 -SiO 2 glasses were prepared using a sol–gel method. These sintered nanoporous Al 2 O 3 -SiO 2 glasses have a transmittance greater than 85 % and possess high mechanical strength, enabling them to contain and protect RE ions. Owing to the presence of nanopores in nanoporous Al 2 O 3 -SiO 2 glasses, Eu ions can easily enter the nanoporous Al 2 O 3 -SiO 2 glasses via an ex-situ dipping method. After drying at room temperature (RT) and then heating at 400 °C, 600 °C, 800 °C, and 1200 °C, we obtained a series of Eu doped nanoporous Al 2 O 3 -SiO 2 glasses. The thermal reduction process from Eu 3+ ions to Eu 2+ ions can occur at a lower sintering temperature (400 °C), enabling a detailed analysis of the thermal reduction mechanism at both low and high temperatures in detail. Under the conditions where Al 3+ ions are present in the samples that are under calcination, Eu 2+ -doped nanoporous Al 2 O 3 -SiO 2 glasses are more easily obtained at relatively low temperatures. Owing to the adjustable composition of Eu 3+ /Eu 2+ in the nanoporous Al 2 O 3 -SiO 2 glasses, tunable emission from red-orange light to blue-violet light can be achieved in the samples. This new type of transparent Eu-doped NPGs has the advantages of high mechanical strength and good processability and is non-toxic and harmless, thereby showing great potential for use in tunable light sources and LED devices.
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
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2024
·
IF 11.2
Jiejun Ren,Longyun Liu,Fan Liu,Huiping Liu,Xiaopeng Zhou,Gen Li,Liangjun Chen,Guoping Yan,Yuhua Wang
Lead halide perovskite (LHP) nanocrystals (NCs) suffer from poor stability against environmental factors (heat, moisture, oxygen, etc.), which seriously hinders their practical application. Constructing a core-shell structure could be an effective approach to improve the stability and optical properties of the LHP NCs. Herein, a novel strategy of water-triggered phase transformation and phospholipid (DSPE) micelle encapsulation is proposed, generating highly luminescent water-dispersed CsPbBr 3 @CsPb 2 Br 5 @DSPE core-shell-shell nanocrystals. The epitaxial growth of the CsPb 2 Br 5 shell is induced by the in-situ reconstruction of the CsPbBr 3 surface by water erosion, and the lattice mismatch with the CsPbBr 3 core is small (3.8%). The further amphipathic phospholipid encapsulation guarantees their excellent water dispersity and stability. Revealed by the femtosecond transient absorption spectroscopy, the dense CsPb 2 Br 5 @DSPE shell effectively passivates the surface of the CsPbBr 3 core, thus improving its stability and luminescence performance. The resulting CsPbBr 3 @CsPb 2 Br 5 @DSPE nanoparticles exhibit excellent performance as fluorescent probes for bioimaging, aqueous inks for high-resolution pattering, and light conversion layers for LEDs, demonstrating their promising potential in multiple applications.
研究领域:
材料科学
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生物医学工程
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Andrei S. Toikka,Ramazan Kenesbay,Maria Baeva,Dmitry M. Mitin,Maria Sandzhieva,Aleksandr Goltaev,Vladimir Fedorov,Alexander Pavlov,Dmitry Gets,Ivan Mukhin,Sergei Makarov
As alternatives to conventional perovskite light-emitting diodes, perovskite light-emitting electrochemical cells (PeLECs) are in great demand in modern science and technology due to their simplified structure and attainable higher luminance. Here, for the first time, we present the implementation and characterization of red CsPbIBr2-based PeLECs/LEDs. To improve perovskite material phase stability, we applied the following strategies for mitigating the mixed anion lead halide perovskite phase segregation: Pb2+ partial substitution by Mn2+, boundary passivation by poly(ethylene oxide) with polyvinylidene fluoride, and two-step thermal treatment with vacuuming and annealing. The complex measurements of photoluminescence, optical density, energy-dispersive X-ray spectroscopy, and X-ray diffraction confirm the minor phase segregation in the optimized perovskite layers. The performed ab-initio calculations predicted the band gaps of perovskite materials with a mixed anion composition, corresponding well to the results of optical measurements. Finally, current and electroluminescence time tracking proved the formation of a dynamic p–i–n structure in the studied PeLEC devices. The developed PeLECs/LEDs exhibited relatively high, for red PeLECs, electroluminescence up to 96 cd m−2 with a peak position at 667–672 nm.
研究领域:
材料科学
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光电技术
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半导体物理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2025
·
IF 3.6
Zihao Han,Zhihao Jiang,Jianwei Dao,Tiqun Wei,Zhenglin Jiang,Zhicheng Lv,Liang Yang
To advance artificial-light plant cultivation and high-performance white light-emitting diodes (LEDs), a phosphor combining excellent luminous thermal stability with superior luminescence is essential. In this work, the high-thermal-stability Ca 3 Bi(PO 4 ) 3 (CBPO): Eu 3+ red phosphors were successfully synthesized via high-temperature solid-state method. The performance of LEDs fabricated with the phosphors is enhanced in the far-red light region. When combined with commercial blue and green phosphors, the resulting white LEDs achieve high color rendering index (R a = 90.3) and low correlated color temperature (CCT = 4898 K). Upon near-ultraviolet (n-UV) excitation, the CBPO: Eu 3+ phosphors exhibit bright red emission at 615 nm, achieving optimal performance at a doping concentration of 0.24. At temperature of 423 K (150 °C), the luminescence intensity of the CBPO: 0.24Eu 3+ phosphor retained 71.9% of room-temperature value, demonstrating its good luminous thermal stability. The fabricated red LEDs with high color purity and spectral characteristics closely matching the absorption properties of plant photosensitive receptor proteins, enhance photosynthetic efficiency and underscore their substantial application potential in plant growth. The fabricated white LEDs can emit bright white light, with R a and R 9 values of 90.3 and 62, which are significantly higher than the standard R a (80) and R 9 (30) of commercial phosphors. We conducted a plant growth experiment in the laboratory, demonstrating that the fabricated red LEDs effectively supplement plant illumination and promote growth. These results demonstrate that the prepared CBPO: Eu 3+ red phosphors hold significant potential for applications in both plant growth lighting and white LEDs.
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Yi Zhang,Peng Wang,Bibo Lou,Shengjie Niu,Haonian Bai,Dan Zhang,Chong-Geng Ma
To fulfill the escalating demand for high-quality white lighting, the exploration of novel and advanced luminescent materials holds a significant role in addressing the issues of reabsorption, color bleaching and deviation in modern WLED solid-state lighting technology based on phosphor-converted materials. In this research, a series of novel Bi 3+ -activated gallium-germanate luminescent materials Sr 2 Ga 2 GeO 7 (SGGO): Bi 3+ were synthesized by means of the classic high-temperature solid-phase method. A comprehensive exploration of their crystal structure, electronic structure, and optical transition properties were conducted through a combined experimental and theoretical calculation analysis. The research outcomes suggest that Bi 3+ , which is prone to occupying Sr sites, shows a remarkable blue emission with a peak at approximately 450 nm throughout the entire spectral range from near ultraviolet (UV) to near infrared when excited at 315 nm, and this is attributed to the 3 P 1 → 1 S 0 transition. Additionally, by devising an efficient energy transfer strategy from Bi 3+ to Eu 3+ , single-component white light can be attained by merely adjusting the doping concentration of Eu 3+ in the SGGO: Bi 3+ , Eu 3+ co-activation system. Eventually, devices packaged based on 310 nm ultraviolet chips also demonstrate the potential application of the synthesized material in WLEDs. These findings contribute to a deeper understanding of the luminescence and energy transfer mechanisms of Bi 3+ -activated systems, and also offer essential guidance for the advancement of high-performance Bi 3+ -doped advanced light-conversion materials and effective materials for various applications demanding enhanced light conversion properties.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）