COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Yongsheng Yang,Siyuan Tang,Da Chen,Changxing Wang,Bingli Gu,Xiameng Li,Feng Xie,Gang Wang,Qinglei Guo
In this study, red-emission graphene quantum dots (R-GQDs), with tunable emission wavelength , are synthesized and explored for applications in trace water sensing, white light emitting diodes (WLEDs) and information encryption . Systematic experiments and characterizations demonstrate that the as-fabricated R-GQDs possess homogeneous size, good crystallinity and high doping concentration of nitrogen and oxygen. Moreover, tunable multicolor light emissions of R-GQDs are demonstrated by simply adjusting the polarity of surrounding solvents. As a result, solid-state fluorescence films are successfully fabricated to construct a high-quality WLED, with the CIE (Commission International d′Eclairage) coordinates (0.352, 0.380) and color temperature of 5121 K. Besides, the water quenchable fluorescence of R-GQDs enables the fabrication of a trace water sensing platform, with the low detection limit of 0.034%. Finally, the potential of our prepared R-GQDs for the application in color visual information encryption is developed. This study may pave the way for the development of GQDs, especially in optically sensing, optoelectronics and anti-counterfeiting technology.
研究领域:
纳米材料学
·
光学传感
·
光电子学
·
分析化学
·
防伪技术
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2018
·Vol. 47
·期 26
·8697-8705
·
IF 4.099
Yang Ding,Jie Liu,Ming Zeng,Xishu Wang,Junli Shi,Weili Wang,Yanru Miao,Xibin Yu
Rare earth (RE3+)-doped NaY(MoO4)2 nanocrystals are efficient materials for realizing multicolor emission, which plays an important role in displays, W-LEDs, solar cells and biolabeling. Up to now, research on the multicolor tuning properties of RE3+-doped NaY(MoO4)2 nanoparticles has mostly focused on traditional preparation routes such as the hydrothermal method and sol–gel process. However, the products obtained using these methods are usually large in size (on the micron/submicron scale) and agglomeration problems are inevitable. With the development of nano optoelectronic devices and bioluminescence labeling, there is an urgent need to find an efficient method to prepare nanoscale, monodispersed and NaY(MoO4)2:RE3+ nanocrystals (NCs) with good crystallinity and stronger emission properties. In this work, we demonstrate a simple, fast, reproducible and one-step synthesis of NaY(MoO4)2:Eu3+ NCs with sizes varying from 1–20 nm via a ligand-assisted reprecipitation strategy. The reaction mechanism and emission intensities of NaY(MoO4)2:Eu3+ NCs with various morphologies have been discussed in detail. Furthermore, Tb3+ and Eu3+ ion co-doped NaY(MoO4)2 NCs were also prepared, and various emission colors were obtained and tuned from red, orange-red, yellow and yellow-green to green. Energy transfer between the Tb3+ and Eu3+ ions in the NaY(MoO4)2 host matrix has also been demonstrated. Finally, a highly efficient and stable NaY(MoO4)2:0.05Tb,0.04Eu NC-based W-LED device was built, which indicates the promising future application for this material in the field of lighting. The tunable multicolour emission, ease of preparation and nanosize reveal that NaY(MoO4)2:RE3+ NCs have a potential application in full color displays and W-LEDs.
研究领域:
材料科学
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纳米技术
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光学材料
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无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
C. Wang,X.Z. Zheng,L. Yue,P.J. Xia,M. Xu,W.B. Dai
The exploration of stable/efficient phosphor for n -UV chip pumped white light-emitting diodes ( w LEDs) remains an arduous task. Herein, a novel series of color tunable Eu 2+ /Tb 3+ /Sm 3+ tridoped Sc-based cyclosilicate phosphors (KBaScSi 3 O 9 : Eu 2+ /Tb 3+ /Sm 3+ ) have successfully designed and obtained via facile solid-state reaction based on comprehensive consideration of rigidly structural network of host, weak electron-phonon coupling strength and spectral adjustability of codopants via energy transfer (ET). The crystallographic occupancies of Eu, Tb and Sm primary in Ba/K, Ba and Ba sites in the monoclinic host, respectively were determined on the basis of the Rietveld refinements and crystal chemistry rules. The photoluminescence (PL) properties were systematically investigated in conjunction with structural analyses, implying that the ‘warm’ white light with excellent thermal stability is stemmed from combination of optimized blue (Eu 2+ ), green (Tb 3+ ) and red (Sm 3+ ) emissions via Eu → Tb → Sm ET strategy. Interestingly, Tb ions play both roles of green light luminescent center and ET bridge to achieve cascade ET for connecting Eu/Sm ion pairs because of the adverse metal-metal charge transfer (MMCT) effect (Eu 2+ + Sm 3+ → Eu 3+ + Sm 2+ ). Furthermore, the phosphor-converted w LEDs (pc- w LEDs), by encapsulating the optimal KBS: 4 %Eu/4 %Tb/6 %Sm with commercial n -UV LED chip, show high thermal stability with satisfactory electroluminescence (EL) performances. These results indicate the KBS: Eu/Tb/Sm phosphors are potential candidates for application in high power n -UV pumped pc- w LEDs.
研究领域:
材料科学
·
发光材料
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固态照明
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无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2023
·Vol. 11
·期 22
·2300888
·
IF 9
Bihao Zhuang,Zicong Jin,Jiahuan Deng,Hui Xiong,Wenzhe Li,Jiandong Fan
Organic-inorganic hybrid metal halide perovskite has played an important role in optoelectronics and photonics due to their extremely high photoluminescence quantum yield (PLQY). However, considering the strong nonmetallic property of antimony (Sb), the excitons in antimony-based single crystals are usually dissipated in the form of non-radiative recombination under organic-inductive effect, which leads to the low PLQY. Herein, two kinds of perovskite-like single crystals, i.e., (8-HQ) 2 SbCl 3 and (8-HQH)SbCl 4 , are innovatively grown. The density functional theory (DFT) calculations reveal that the unique luminescence characteristics are associated with the inductive effect of organic coordination and exciton effect in the metal octahedral skeleton. When Cl − replaces the organic ligand in (8-HQ) 2 SbCl 3 , the inductive effect is reduced while the self-trapped exciton effect in the metal octahedron is enhanced. Besides, the theoretical research on electron transmission in a modeling device reveals that the hydrogen bond of organic A-site in the single crystal promotes the transition of electrons. Based on the luminescent properties of (8-HQH)SbCl 4 , the white LED devices are obtained by coating (8-HQH)SbCl 4 and red phosphor on 450 nm LED chips.
研究领域:
材料科学
·
光电子学
·
凝聚态物理
·
无机化学
·
半导体器件
·
光学材料
·
晶体工程
✓ 已验证
DOI
高影响因子
Small
·
2019
·Vol. 15
·期 19
·1900484
·
IF 10.856
Xiaosheng Tang,Weiwei Chen,Zhengzheng Liu,Juan Du,Zhiqiang Yao,Yi Huang,Cheng Chen,Zhaoqi Yang,Tongchao Shi,Wei Hu,Zhigang Zang,Yu Chen,Yuxin Leng
All-inorganic semiconductor perovskite quantum dots (QDs) with outstanding optoelectronic properties have already been extensively investigated and implemented in various applications. However, great challenges exist for the fabrication of nanodevices including toxicity, fast anion-exchange reactions, and unsatisfactory stability. Here, the ultrathin, core–shell structured SiO 2 coated Mn 2+ doped CsPbX 3 (X = Br, Cl) QDs are prepared via one facile reverse microemulsion method at room temperature. By incorporation of a multibranched capping ligand of trioctylphosphine oxide, it is found that the breakage of the CsPbMnX 3 core QDs contributed from the hydrolysis of silane could be effectively blocked. The thickness of silica shell can be well-controlled within 2 nm, which gives the CsPbMnX 3 @SiO 2 QDs a high quantum yield of 50.5% and improves thermostability and water resistance. Moreover, the mixture of CsPbBr 3 QDs with green emission and CsPbMnX 3 @SiO 2 QDs with yellow emission presents no ion exchange effect and provides white light emission. As a result, a white light-emitting diode (LED) is successfully prepared by the combination of a blue on-chip LED device and the above perovskite mixture. The as-prepared white LED displays a high luminous efficiency of 68.4 lm W −1 and a high color-rendering index of Ra = 91, demonstrating their broad future applications in solid-state lighting fields.
研究领域:
材料科学
·
纳米技术
·
光电子学
·
半导体物理
·
固体照明
·
无机化学
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2015
·
IF 3.368
Xiang Shen,Bing Yan
A series of luminescent Ln 3+ @bio-MOF-1 (Ln = Eu, Tb, bio-MOF-1 = Zn 8 (ad) 4 (BPDC) 6 O⋅2Me 2 NH 2 (ad = adeninate, BPDC = biphenyldicarboxylate)) are synthesized via postsynthetic cation exchange by encapsulating lanthanide ions into an anionic metal–organic framework (MOF), and their photophysical properties are studied. After loading 2-thenoyltrifluroacetone (TTA) as sensitized ligand by a gas diffusion (“ship-in-bottle”) method, it is found that the luminescent intensity of Eu 3+ is enhanced. Especially, when loading two different lanthanide cations into bio-MOF-1, the luminescent color can be tuned to close white (light pink) light output. Additionally, bio-MOF-1 and Eu 3+ @bio-MOF-1 are selected as representative samples for sensing metal ions . When bio-MOF-1 is immersed in the aqueous solutions of different metal ions , it shows highly sensitive sensing for Fe 3+ as well as Eu 3+ @bio-MOF-1 immersed in the DMF solutions of different metal ion. The results are benefit for the further application of functionalized bio-MOFs in practical fields.
研究领域:
无机化学
·
材料科学
·
分析化学
·
纳米生物技术
·
光物理学
·
配位化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）