Journal of Materials Chemistry C
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2019
·Vol. 7
·期 30
·9167-9174
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IF 6.641
Chong Li,Baojun Ding,Lijing Zhang,Kepeng Song,Shengyang Tao
Organometal halide perovskite nanocrystals have received extensive attention as a high-performance photoelectric conversion material. However, the perovskite nanocrystals prepared by the traditional batch reactor have uncontrollable size and optical properties, low utilization of raw materials, and complicated purification treatment. In this paper, a flow microreactor is designed with the assistance of finite element analysis and realized the continuous synthesis of CH3NH3PbX3 nanocrystals with a 100% yield. The average size of the prepared nanocrystalline grains is as low as 3.9 nm without any purification step. The prepared nanocrystals have narrow-band emission characteristics (the full width at half-maximum is down to 18 nm), and the quantum yield can reach 76.9%. It is also possible to prepare CH3NH3PbX3 (X = Br, I) nanocrystals covering different emission wavelengths in the visible light region by this method. The coating of a polystyrene film improved the stability of the perovskite nanocrystals. The flexible hybrid film is applied to modify a LED device, and a white LED luminescence spectrum is obtained.
研究领域:
材料科学
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纳米技术
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光电子学
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化学工程
✓ 已验证
DOI
高影响因子
ACS Nano
·
2015
·
IF 12.881
Feng Zhang,Haizheng Zhong,Cheng Chen,Xian-gang Wu,Xiangmin Hu,Hailong Huang,Junbo Han,Bingsuo Zou,Yuping Dong
Organometal halide perovskites are inexpensive materials with desirable characteristics of color-tunable and narrow-band emissions for lighting and display technology, but they suffer from low photoluminescence quantum yields at low excitation fluencies. Here we developed a ligand-assisted reprecipitation strategy to fabricate brightly luminescent and color-tunable colloidal CH3NH3PbX3 (X = Br, I, Cl) quantum dots with absolute quantum yield up to 70% at room temperature and low excitation fluencies. To illustrate the photoluminescence enhancements in these quantum dots, we conducted comprehensive composition and surface characterizations and determined the time- and temperature-dependent photoluminescence spectra. Comparisons between small-sized CH3NH3PbBr3 quantum dots (average diameter 3.3 nm) and corresponding micrometer-sized bulk particles (2–8 μm) suggest that the intense increased photoluminescence quantum yield originates from the increase of exciton binding energy due to size reduction as well as proper chemical passivations of the Br-rich surface. We further demonstrated wide-color gamut white-light-emitting diodes using green emissive CH3NH3PbBr3 quantum dots and red emissive K2SiF6:Mn4+ as color converters, providing enhanced color quality for display technology. Moreover, colloidal CH3NH3PbX3 quantum dots are expected to exhibit interesting nanoscale excitonic properties and also have other potential applications in lasers, electroluminescence devices, and optical sensors.
研究领域:
材料科学
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纳米技术
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光电子学
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显示技术
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光子学
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2018
·
IF 4.484
Zhao Zhenfu,Wu Zhihai,Cheng Jiong,Jing Liang,Hou Yafei
Organometal halide perovskite quantum dots (PQDs) have recently received much attention as a very promising family of materials with excellent performance in electronic and optoelectronic fields, but these perspectives are being restrained by the severe stability, such as chemical and optical degradations. Herein, we propose and demonstrate a facile solution synthesis of nanocomposites of CH3NH3PbX3 (X = Cl, Br, I) PQDs embedded in magnesium silicate hollow spheres. The resultant nanocomposites preserved the strong photoluminescence of the CH3NH3PbX3 PQDs, and the emission peak can be tunable from blue to red region. Photostability tests demonstrated that the nanocomposite samples were obviously more stable than the bare CH3NH3PbX3 PQDs. The photoluminescence (PL) of the nanocomposite sample still remained at 80% after 72 h UV LED illumination, which was much higher than the remnant PL (30%) of the pure CH3NH3PbX3 PQDs. With their high thermal stability and photostability, we demonstrated that these nanocomposites can be used as phosphors in an on-chip UV LED for multicolor display. It offers a facile method to protect perovskite quantum dots and may have great potential applications in solid-state lighting systems with demand of high-color quality such as lasers, displays, and light-emitting diodes.
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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显示技术
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2021
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IF 3.882
Sai-Nan Guo,Hao Wu,Dan Wang,Jie-Xin Wang
Lead halide perovskite quantum dots (QDs) are known as prospective optoelectronic device materials because of their excellent luminescence, extraordinary photoelectric performance, and specific octahedron framework. Herein, we report a cost-effective approach for synthesizing highly stable CH3NH3PbBr3 QDs in low-polarity binary solvents without nitrogen protection. The CH3NH3PbBr3 QDs are tunable from 1.2 to 4.2 nm by adjusting the proportion of oleic acid and oleylamine as capping ligands. The photoluminescence quantum yield of CH3NH3PbBr3 QDs can reach 87.4%. The fluorescence can maintain over 80% of its earliest emission intensity under the atmosphere after 5 days, which is much better than that (∼10%) of QDs with ligand-assisted reprecipitation. The possible reaction mechanism of preparing CH3NH3PbBr3 QDs was also addressed. Notably, such a strategy can be applied extensively in the preparation of other lead halide perovskite QDs. Furthermore, the as-prepared thick PMMA-coated CH3NH3PbBr3 QDs were further conjoined with a red luminescence powder on a blue InGaN chip to obtain a powerful efficiency (45.4 lm W–1) warm white light-emitting diode.
研究领域:
材料科学
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光学工程
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化学
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2015
·Vol. 27
·期 35
·5176-5183
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IF 17.493
Liu Y,Yang Z,Cui D,Ren X,Sun J,Liu X,Zhang J,Wei Q,Fan H,Yu F,Zhang X,Zhao C,Liu SF.
Two-inch-sized perovskite crystals, CH3 NH3 PbX3 (X=I, Br, Cl), with high crystalline quality are prepared by a solution-grown strategy. The availability of large perovskite crystals is expected to transform its broad applications in photovoltaics, optoelectronics, lasers, photodetectors, LEDs, etc., just as crystalline silicon has done in revolutionizing the modern electronics and photovoltaic industries.
研究领域:
材料科学
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光电子学
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光伏技术
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晶体生长
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半导体物理
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
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2019
·
IF 2.961
Yanchun Yang,Song Wei,Xiaojiao Kang,O. Tegus,Daocheng Pan
Employing the short-chain C 4 H 9 NH 3 X (X = Cl, Br, I) compound as the unique capping agent, highly quality CH 3 NH 3 PbX 3 (X = Cl, Br, I) perovskite quantum dots can be synthesized at room temperature in the open air, which possess high photoluminescence quantum yields and tunable emission in the range of 440–660 nm. Besides, C 4 H 9 NH 3 Br can also improve the morphology of CH 3 NH 3 PbBr 3 thin films by spin-coating the N, N -dimerthylformamide solution of CH 3 NH 3 Br, C 4 H 9 NH 3 Br and PbBr 2 , making the thin film dense and compact, and improving its optical properties .
研究领域:
材料科学
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纳米科技
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光电功能材料
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半导体物理
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凝聚态物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）