Advanced Optical Materials
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2019
·Vol. 7
·期 18
·1900330
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IF 7.125
Yong Ge,Mengjiao Zhang,Lei Wang,Linghai Meng,Jialun Tang,Yu Chen,Lingxue Wang,Haizheng Zhong
Polarization can be used to distinguish artificial objects in complicated environments. The development of polarization-sensitive detection at ultraviolet (UV) wavelengths has been substantially delayed by the difficulties in fabricating anisotropic materials and optical elements for polarization modulation. Polarization-sensitive UV detection is developed by combining an electron-multiplying charge-coupled device (EMCCD) with a polarized luminescence downshifting material that benefits from an oriented-CdSe@CdS-dot-in-rods-embedded polyvinylidene fluoride (PVDF) composite film. With mechanical-stretching-induced orientation, the composite film shows emission polarization with an optimized ratio up to 0.52 ± 0.02. This integrated detection system can respond to linearly polarized 405 nm light with a signal difference up to 23%, showing its potential for use in UV polarization-enhanced imaging for object recognition.
研究领域:
光电子学
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纳米材料
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偏振成像
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光电探测器
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紫外传感
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DOI
高影响因子
CHINESE CHEMICAL LETTERS
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2016
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IF 1.947
Li-Li Xi,Hong-Bing Ma,Guan-Hong Tao
CdSe/CdS quantum dots (QDs) functionalized by thiourea (TU) were synthesized and used as a fluorescent sensor for mercury ion detection. The TU-functionalized QDs were prepared by bonding TU via electrostatic interaction to the core/shell CdSe/CdS QDs after capping with thioglycolic acid (TGA). It was observed that the fluorescence of the functionalized QDs was quenched upon the addition of Hg 2+ . The quantitative detection of Hg 2+ with this fluorescent sensor could be conducted based on the linear relationship between the extent of quenching and the concentration of Hg 2+ added in the range of 1–300 μg L −1 . A detection limit of 0.56 μg L −1 was achieved. The sensor showed superior selectivity for Hg 2+ and was successfully applied to the determination of mercury in environmental samples with satisfactory results.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
Journal of the American Chemical Society
·
2016
·
IF 13.038
Jianhai Zhou,Chaodan Pu,Tianyu Jiao,Xiaoqi Hou,Xiaogang Peng
CdSe magic-size clusters with close-shell surface and fixed molecular formula are well-known in the size range between ∼1 and 3 nm. By applying high concentration of cadmium alkanoates as ligands, a conventional synthetic system for CdSe nanocrystals was tuned to discriminate completion from initiation of atomic flat facets. This resulted in ∼4–13 nm CdSe nanocrystals with hexahedral shape terminated with low-index facets, namely three (100), one (110), and two (111) facets. These low-symmetry (Cs group with single mirror plane) yet monodisperse hexahedra were found to be persistent not only in a broad size range but also under typical synthetic temperatures for growth of both CdSe and CdS. Atomic motion on the surface of the nanocrystals under enhanced ligand dynamics initiated intraparticle ripening without activating interparticle ripening, which converted the hexahedral nanocrystals to monodisperse spherical ones. This new synthetic strategy rendered optimal color purity of photoluminescence (PL) of the CdSe and CdSe/CdS core/shell nanocrystals, with the ensemble PL peak width comparable with that of a corresponding single dot.
研究领域:
材料科学
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纳米技术
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DOI
PubMed
高影响因子
TALANTA
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2016
·
IF 4.035
Fang Gao,Shiyao Ma,Xincai Xiao,Yan Hu,Dan Zhao,Zhike He
Despite of the importance of enantiomers , the fluorescence sensing of enantiomers and the interpretation of the “preferential interaction” still remain insufficiently explored. In this study, we report the recognition of tyrosine (Tyr) enantiomers by chiral N -acetyl- L -cysteine ( L -NAC) capped CdSe/CdS quantum dots (QDs) under alkaline experimental condition. L -Tyr could greatly quench the fluorescence of CdSe/CdS QDs, while D -Tyr displayed no effect on the fluorescence. The one-step synthesized chiral L -NAC-CdSe/CdS QDs demonstrated high selectivity for Tyr enantiomers. In particular, the mechanism of chiral recognition has been studied by UV/vis absorption spectra and circular dichroism (CD) spectra. The changes of intensity and sign of CD spectra corroborated the attachment of L -Tyr to the surface of QDs, which may be valuable aids in obtaining a better understanding of the possible mechanism of enantioselective recognition.
研究领域:
分析化学
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生物化学
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纳米材料科学
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Hongyue Wang,Yangyang Guo,Hongxing Hao,Hongtao Bian,Herve Aubin,Yang Wei,Huixin Li,Taihong Liu,Aloyse Degiron,Hongqiang Wang
Addressing the interactions between optical antennas and ensembles of emitters is particularly challenging. Charge transfer and Coulomb interactions complicate the understanding of the carrier dynamics coupled by antennas. Here, we show how Au antennas enhance the luminescence of CdSe/CdS quantum dot assemblies through carrier dynamics control within the framework of the local Kirchhoff law. The Au antennas inject hot electrons into quantum dot assemblies via plasmon-induced hot electron transfer that increases the carrier concentration. Also, the localized surface plasmon resonances of Au antennas favorably tilt the balance between nonradiative Auger processes and radiative recombination in the CdSe core. Eventually, a high bright (125,091.6 cd/m2) deep-red quantum dot light-emitting diode is obtained by combining with Au antennas. Our findings suggest a new understanding of light emission of assembled emitters coupled by antennas, which is of essential interest for the description of light–matter interaction in advanced optoelectronics.
研究领域:
光学
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材料科学
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纳米技术
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DOI
高影响因子
Laser & Photonics Reviews
·
2025
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IF 10
Xuting Chen,Linqi Chen,Yuan Jiang,Yijing Wang,Hongbing Li,Jingzhou Li,Xinjie Li,Zeyi Wang,Hongxing Dong,Long Zhang
Fluorescent antennas (FAs) serve as promising optical concentrators for optical wireless communication (OWC) by overcoming the Étendue limit. Quantum dots-polymer nanocomposites exhibit superior optical properties for FAs. However, the poor chemical affinity between the surface ligands of quantum dots (QDs) and the polar functional groups in polymer matrices reduces interfacial compatibility, triggering ligand desorption and interparticle aggregation during photopolymerization. These effects severely degrade the photoluminescence efficiency and long-term stability, thus limiting the practical application of polymer-based FAs. Herein, a high-performance nanocomposite is demonstrated by embedding ODPA-passivated CdSe/CdS QDs into a polyurethane acrylate (PUA) matrix through doctor-blade coating and photopolymerization. Molecular dynamics simulations and density functional theory calculations reveal that QDs improve interfacial compatibility with PUA matrix through hydrogen-bond crosslinking between surface ligands and PUA hard segments, along with alkyl chain-induced plasticization of soft segments. Optimizing the QD concentration results in nanocomposites with a near-unity photoluminescence quantum yield of 99.15% and enhanced environmental stability. The sandwich-structured FA demonstrates a −3 dB bandwidth of 8.6 MHz, a 154 Mbps data rate using orthogonal frequency division multiplexing (OFDM) modulation. This work presents a readily processable nanocomposite system with high efficiency and stability, advancing OWC applications in terrestrial and underwater environments.
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产品关联
DOI
高影响因子
Journal of Nanomaterials
·
2020
·
IF 1.98
Shibing Zou,Feng Li
Highly efficient all-inorganic perovskite solar cells require a fast charge transfer from CsPbBr3 to TiO2 to reduce the recombination from trap states. Herein, we insert a CdS/CdSe/CdS quantum dot (QD) layer between the TiO2 and CsPbBr3 layers to fabricate all-inorganic perovskite solar cells. By tuning the thicknesses of the CdSe layer of CdS/CdSe/CdS QDs, the conduction band (CB) levels can be adjusted to -3.72~-3.87 eV. After inserting the QD intermediate layer, the energy offset between the CB of TiO2 and CsPbBr3 is reduced, thus leading to a charge transfer rate boost from to . The power conversion efficiency (PCE) of the solar cell with QD intermediate layer achieves 8.64%, which is 20% higher than its counterpart without QDs.
研究领域:
材料科学
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光伏技术
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产品关联
DOI
高影响因子
Advanced Electronic Materials
·
2021
·Vol. 7
·期 7
·2000965
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IF 7.295
Zuoliang Wen,Pai Liu,Jingrui Ma,Siqi Jia,Xiangtian Xiao,Shihao Ding,Haodong Tang,Hongcheng Yang,Chaojian Zhang,Xiangwei Qu,Bing Xu,Kai Wang,Kie Leong Teo,Xiao Wei Sun
Colloidal nanoplatelets (NPLs) are an emerging semiconductor nanocrystal in the display community due to their ultranarrow emission linewidth. Herein, an ultrapure green emitting nanocrystal light-emitting diode (LED) based on four-monolayer CdSe/CdS core/crown NPLs is developed. By applying the nonstacked nanoplates, the nonradiative energy transfer in the NPLs film is successfully suppressed. The nonstacked NPL-LEDs with pure green emission of 521.5 nm exhibit a low turn-on voltage of 2.1 V, a maximum luminance of 22 400 cd m −2 , a peak external quantum efficiency (EQE) of 2.16%, which is a sixfold enhancement comparing to the stacked NPL-LED (EQE = 0.34%). This work demonstrates the potential of core/crown NPLs for ultrawide color gamut displays.
研究领域:
材料科学
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光学工程
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DOI
高影响因子
Journal of the American Chemical Society
·
2023
·
IF 15
Xiaolan Zhou,Chaodan Pu
Surface reconstruction can rearrange the surface atoms of a crystal without the need of growth processes and has the potential to synthesize crystals with novel morphologies and facets that cannot be obtained through regular synthesis. However, little is known about the molecular mechanisms of the surface reconstruction process. Here, utilizing surface reconstruction, we report the synthesis of nonpolar facets (110) facets)-terminated dodecahedral zinc-blende CdSe/CdS core/shell quantum dots. The morphology transformation is achieved by first fully exchanging the cadmium carboxylate ligand with oleylamine and then undergoing surface reconstruction. The surface reconstruction-induced morphology transformation is confirmed by transmission electron microscopy and absorption spectroscopy. Details of kinetic experiments and simulation results demonstrated that successful surface reconstruction must be assisted by a proton shuttle. Except for the first report on zinc-blende quantum dots terminated with (110) facets, the surface reconstruction aided by the proton shuttle offers valuable insights for devising methods to regulate the properties of nanocrystals.
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DOI
PubMed
高影响因子
Toxics
·
2022
·Vol. 10
·期 7
·367
·
IF 4.472
Dengpeng Wang,Feng Gao,Xianran Wang,Xiaomei Ning,Kaituo Wang,Xinpeng Wang,Yuezhou Wei,Toyohisa Fujita
The detection of heavy metals in aqueous solutions has always attracted much attention from all over the world. A fluorescent probe of CdSe/CdS core-shell quantum dots (QDs) was designed to detect trace Cd2+in aqueous solutions using the OFF–ON mode rapidly and efficiently, likely based on adsorption and desorption reactions between ethylenediaminetetraacetic acid disodium salt (EDTA) and CdSe/CdS QDs. In the OFF mode, the optical shielding function of EDTA results in fluorescence quenching owing to the strong adsorption ability of EDTA with Cd2+on the sites of CdSe/CdS QDs surface. In the ON mode, the introduction of Cd2+promotes the desorption of EDTA from the EDTA-CdSe/CdS QDs and restores the fluorescence intensity. There were two linear response ranges which were 0.1–20 µmol/L and 20–90 µmol/L for the EDTA-CdSe/CdS system to detect Cd2+. The detection limit was 6 nmol/L, and the standard deviation was below 4% for the detection of Cd2+concentration in tap water.Keywords:QDs;fluorescence quenching;fluorescence restore;Cd2+detection;adsorption;desorption
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 29
·期 21
·18059-18066
·
IF 2.324
Li Zhen,Yu Libo,Song Hai,Feng Lei,Wang Xingpeng
TiO 2 nanoparticles (NP) at top of TiO 2 nanotube (TiO 2 NP@TiO 2 NT) double-layered architecture is constructed to combine the advantages of TiO 2 NP and TiO 2 NT together. This composite TiO 2 NP@TiO 2 NT architecture as photoanode possesses a larger surface area for more QDs loading, and highly tubular structure for electron swift transport. Based on this architecture, CdSe/CdS quantum dots (QDs) have been successfully synthesized by successive ionic layer adsorption reaction (SILAR) method for quantum dots-sensitized solar cell application. The photovoltaic performance of QDSSCs based on TiO 2 NP@TiO 2 NT have been investigated in contrast with bare TiO 2 NP and bare TiO 2 NT architectures with almost the same thickness. The results show that the power conversion efficiency (PCE) of QDSSCs could be enhanced using TiO 2 NP@TiO 2 NT and improved to 3.26%, which is 80% and 38% higher than QDSSCs based on bare TiO 2 NT and bare TiO 2 NP, respectively. The BET surface area, UV–vis absorption spectra, and incident photon to current conversion efficiency (IPCE) measurements results show the evidence that the TiO 2 NP@TiO 2 NT can combine advantages of TiO 2 NP and TiO 2 NT structures together and lead to a higher light harvesting efficiency, electron collecting efficiency, and efficient electron transport.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-8
·
IF 14.7
Wang Xingzhi,Gao Yan,Liu Xiaonan,Xu Huaiyu,Liu Ruixiang,Song Jiaojiao,Li Bo,Shen Huaibin,Fan Fengjia
High-energy exciton emission could allow single-component multi-colour display or white light-emitting diodes. However, the thermal relaxation of high-energy excitons is much faster than the photon emission of them, making them non-emissive. Here, we report quantum dots with light hole-heavy hole splitting exhibiting strong high-energy exciton electroluminescence from high-lying light holes, opening a gate for high-performance multi-colour light sources. The high-energy electroluminescence can reach 44.5% of the band-edge heavy-hole exciton emission at an electron flux density Φ e of 0.71 × 10 19 s −1 cm −2 − 600 times lower than the photon flux density Φ p (4.3 × 10 21 s −1 cm −2 ) required for the similar ratio. Our simulation and experimental results suggest that the oscillator strength of heavy holes reduces more than that of light holes under electric fields. We attribute this as the main reason for strong light-hole electroluminescence. We observe this phenomenon in both Cd x Zn 1-x Se-ZnS and CdSe-CdS core-shell quantum dots exhibiting large light hole-heavy hole splittings.
研究领域:
材料科学
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光电技术
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纳米技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）