ACS Applied Nano Materials
·
2024
·
IF 5.3
Li Luo,Zhen Fan,Zhaobin Zhang,Danyang Liu,Guofa Li,Lishuang Wang,Bingsuo Zou
SnO2 nanoparticles (NPs) have been used as an electron transport layer (ETL) in quantum dot light-emitting diodes (QLEDs) to achieve stable and high-performance devices. However, SnO2 NPs with high electron mobility cause the problem of imbalanced charge injection and transport in QLEDs. Meanwhile, the SnO2 NPs synthesized at low temperature have hydroxyl (−OH) groups, which could damage the performance of QLEDs. Here, Zn doping was applied to modulate the properties of SnO2 NPs and achieve better carrier balance in green CdSe/ZnS QLED. The maximum current efficiency (CE) of QLED with 5 wt % Zn-doped SnO2 NPs is 2.3-fold higher than that of SnO2-based QLED. In addition, a small-molecule 4,4′-bis(carbazole-9-yl)-1,1′-biphenyl (CBP)-mixed poly(9-vinylcarbazole) (PVK) layer was used as a hole transport layer to facilitate the hole injection and charge balance. As a result, a maximum external quantum efficiency (EQE) of 5.03% is obtained for the best performance device. The T50 lifetime at a luminance of 100 cd/m2, for a device based on 5 wt % Zn-doped SnO2 ETL, is 9141 h, which is 2.29-fold longer than the reference one. This work provides a new strategy to obtain high-performance and stable display arrays.
研究领域:
材料科学
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光电子学
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纳米技术
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL PHYSICS
·
2024
·Vol. 160
·期 23
·
IF 3.1
Zhu Hongmei,Wang Qingqian,Chen Wei,Sun Kun,Zhong Huaying,Ye Taikang,Wang Zhaojin,Zhang Wenda,Müller-Buschbaum Peter,Sun Xiao Wei,Wu Dan,Wang Kai
Chiral perovskite materials are being extensively studied as one of the most promising candidates for circularly polarized luminescence (CPL)-related applications. Balancing chirality and photoluminescence (PL) properties is of great importance for enhancing the value of the dissymmetry factor ( g lum ), and a higher g lum value indicates better CPL. Chiral perovskite/quantum dot (QD) composites emerge as an effective strategy for overcoming the dilemma that achieving strong chirality and PL in chiral perovskite while at the same time achieving high g lum in this composite is very crucial. Here, we choose diphenyl sulfoxide (DPSO) as an additive in the precursor solution of chiral perovskite to regulate the lattice distortion. How structural variation affects the chiral optoelectronic properties of the chiral perovskite has been further investigated. We find that chiral perovskite/CdSe–ZnS QD composites with strong CPL have been achieved, and the calculated maximum | g lum | of the composites increased over one order of magnitude after solvent-additive modulation (1.55 × 10 −3 for R-DMF/QDs, 1.58 × 10 −2 for R-NMP-DPSO/QDs, −2.63 × 10 −3 for S-DMF/QDs, and −2.65 × 10 −2 for S-NMP-DPSO/QDs), even at room temperature. Our findings suggest that solvent-additive modulation can effectively regulate the lattice distortion of chiral perovskite, enhancing the value of g lum for chiral perovskite/CdSe–ZnS QD composites.
研究领域:
材料科学
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光电
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纳米技术
·
化学
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产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2014
·Vol. 7
·期 4
·1395-1400
·
IF 1.938
Li Wang,Di Luo,Dongdong Qin,Duoliang Shan,Xiaoquan Lu
This paper reports the electrochemiluminescence (ECL) behavior of CdSe/ZnS with K2S2O8 as the coreactant. The effects of pH, K2S2O8 concentration, the duration of the reaction of 4-ATP with GCE and the duration of the reaction of 4-ATP/GCE with QDs on ECL intensity were studied in detail. A possible ECL reaction mechanism was then proposed. In addition, it was observed that the ECL intensity was efficiently quenched by trace amounts of heavy metal ion. Based on the quenching effect of Pb2+ upon the ECL of CdSe/ZnS QDs, a QDs-ECL sensor was constructed to detect Pb2+ in preserved duck egg. The sensor showed good reproducibility and stability.
研究领域:
分析化学
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电化学
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环境科学
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材料科学
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产品关联
DOI
高影响因子
Analytical Methods
·
2018
·Vol. 10
·期 29
·3582-3588
·
IF 2.073
Jieying Li,Mao Mao,Feng Wu,Qiang Li,Luyao Wei,Lan Ma
In this study, highly fluorescent amino-functionalized CdSe/ZnS core/shell quantum dots (CdSe/ZnS QDs) coated with amphiphilic N-alkylated poly(ethyleneimine) have been synthesized and applied as fluorescent probes in lateral flow immunoassay (LFIA) strips for on-site determination of aflatoxin B1 (AFB1). The amino-functionalized QDs were used to combine with anti-AFB1 via thiol-maleimide conjugation and they effectively enhanced the detection sensitivity. The test strip had high sensitivity for AFB1 from 0.001 ng mL−1 to 10 ng mL−1 with a low limit of detection (LOD) of 0.005 ng mL−1, which was much lower than the allowable concentration by the European Commission (EC) (2.0 μg kg−1) and FDA (20 μg kg−1). The IC50 value was calculated to be 0.025 ng mL−1. The reproducibility and recovery tests showed that the quantitative results were accurate, and it could be used for rapid on-site detection of AFB1 in cereal products.
研究领域:
分析化学
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食品安全
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纳米技术
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毒理学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 1
·1-10
·
IF 5.479
Wen Shao-Hua,Liang Ru-Ping,Zeng Hui-Hui,Zhang Li,Qiu Jian-Ding
A ratiometric fluorometric method is described for the determination of arsenate via its inhibitory effect on the activity of the enzyme acid phosphatase. A nanoprobe was designed that consists of CdSe/ZnS quantum dots (QDs) coated with the terbium(III) complex of guanosine monophosphate (Tb-GMP). The nanoprobe was synthesized from carboxylated QDs, Tb(III) and GMP via binding of Tb(III) by both the carboxy and the phosphate groups. The nanoprobe, under single-wavelength excitation (at 280 nm), displays dual (red and green) emission, with peaks at around 652 nm from the QDs, and at 547 nm from the Tb-GMP coordination polymers. It is shown to be a viable nanoprobe for fluorometric determination of As(V) detection through it inhibitory action on the activity of acid phosphatase (ACP). The enzyme destroys the Tb-GMP structure via hydrolysis of GMP, and hence the fluorescence of the Tb-GMP complex is quenched. In contrast, the fluorescence of the CdSe/ZnS QDs remains inert to ACP. It therefore can serve as an internal reference signal. In the presence of arsenate (an analog of phosphate), the activity of ACP is inhibited due to competitive binding. Thus, hydrolysis of GMP is prevented. These findings were used to design a ratiometric fluorometric method for the quantification of As(V). The ratio of fluorescences at 547 and 652 nm increases linearly in the 0.5 to 200 ppb As(V) concentation range, and the limit of detection is 0.39 ppb. Under a UV lamp, the probe shows distinguishable color from green to red on increasing the concentration of As(V).
Schematic illustration of CdSe/ZnS quantum dot coated with carboxy-PEG and modified with the terbium(III)-GMP complex as a fluorescent nanoprobe for ratiometric determination of arsenate via its inhibition of ACP activity.
研究领域:
生物化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
Progress in Natural Science-Materials International
·
2022
·
IF 4.269
Xue Li,Jinhua Li,Wentao Yang,Dandan Han,Na Yao,Hongbin Zhao,Xueying Chu,Xuemei Liang,Chunguang Bi,Chunfeng Wang,Guilian Yang
An ultrasensitive and selective sandwich-type fluorescent immunosensor based on fluorescence resonance energy transfer (FRET) between CdSe/ZnS quantum dots (QDs) and Au nanorods (AuNRs) was developed for the rapid detection of porcine reproductive and respiratory syndrome virus (PRRSV). Modified CdSe/ZnS QDs and AuNRs were bioconjugated with primary antibodies M and GP5, respectively. When the target antigen was present, a well-known sandwich-type form CdSe/ZnS QDs-M antibody-antigen-GP5 antibody-AuNRs was produced, and thus reducing the distance between the QDs and NRs. As a result, FRET occurred and the fluorescence intensity of CdSe/ZnS QDs decreased, and this decrease was used to determine the antigen concentration. Ultrasensitive detection of PRRSV at low concentrations in swine serum was achieved with a limit of detection of 0.55 TCID 50 /mL and a linear detection range of 10 1 –3.5 × 10 4 TCID 50 /mL. Therefore, the fluorescent immunosensor is selective and highly sensitive; specifically, it can detect PRRSV at low concentrations in swine serum over a large concentration range. This proposed detection method can facilitate the development of high-performance fluorescent immunosensors for the detection of PRRSV and other antigens.
研究领域:
生物传感器
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纳米技术
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病毒学
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兽医学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2021
·Vol. 32
·期 17
·22024-22034
·
IF 2.478
Li Hong,Jiao Jinxu,Ye Qi,Wu Zhixin,Luo Donglian,Xiong Dehua
Quantum dots (QDs) attract extensive attention because of their excellent optoelectronic performance. However, few research has been done on the synthesis of core–shell QDs by one-step thermal injection. Here the CdSe/ZnS core–shell QDs were successfully synthesized by a one-step thermal injection method. The synthesis process of CdSe/ZnS core–shell QDs was investigated from two aspects of reaction time and oleic acid dosage. The results suggest that the reaction time and the dosage of oleic acid have important effects on the optical properties of CdSe/ZnS core–shell QDs. The action mechanism of oleic acid was also explained in this paper. Moreover, highly efficient green quantum dot light-emitting diodes (QLEDs) were fabricated with CdSe/ZnS core–shell QDs on ITO glass substrate by rotary coating method. The minimum starting voltage of 1.91 V and the maximum brightness of 12,057 cd m −2 were achieved in the QLEDs. This study is of great significance for the development of the synthesis of core–shell QDs by one-step thermal injection and QLEDs.
研究领域:
材料科学
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纳米技术
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光电技术
·
半导体物理
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2025
·Vol. 15
·期 15
·1189
·
IF 4.3
Yuan-Yuan Liu,Yong-Yue Sun,Yuan Guo,Lu-Lu Chen,Jun-Hao Guo,Haifang Wang
The biological effects of nanoparticles are closely related to their intracellular content and location, both of which are influenced by various factors. This study investigates the effects of surface charge on the uptake, intracellular distribution, and exocytosis of CdSe/ZnS quantum dots (QDs) in Raw264.7 macrophages. Negatively charged 3-mercaptopropanoic acid functionalized QDs (QDs-MPA) show higher cellular uptake than positively charged 2-mercaptoethylamine functionalized QDs (QDs-MEA), and serum enhances the uptake of both types of QDs via protein corona-mediated receptor endocytosis. QDs-MEA primarily enter the cells through clathrin/caveolae-mediated pathways and predominantly accumulate in lysosomes, while QDs-MPA are mainly internalized through clathrin-mediated endocytosis and localize to both lysosomes and mitochondria. Exocytosis of QDs-MPA is faster and more efficient than that of QDs-MEA, though both exhibit limited excretion. In addition to endocytosis and exocytosis, cell division influences intracellular QD content over time. These results reveal the charge-dependent interactions between QDs and macrophages, providing a basis for designing biocompatible nanomaterials.
研究领域:
纳米技术
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细胞生物学
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材料科学
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生物医学工程
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毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Nanomedicine
·
2018
·
IF 4.37
Fei Yu,Ya-min Xiong,Song-cheng Yu,Lei-liang He,Shan-shan Niu,Yu-ming Wu,Jie Liu,Ling-bo Qu,Li-e Liu,Yong-jun Wu
Background DNA methyltransferase 1 (DNMT1), a dominant enzyme responsible for the transfer of a methyl group from the universal methyl donor to the 5-position of cytosine residues in DNA, is essential for mammalian development and closely related to cancer and a variety of age-related chronic diseases. DNMT1 has become a useful biomarker in early disease diagnosis and a potential therapeutic target in cancer therapy and drug development. However, till now, most of the studies on DNA methyltransferase (MTase) detection have focused on the prokaryote MTase and its activity. Methods A magnetic fluorescence-linked immunosorbent assay (FLISA) using CdSe/ZnS quantum dots as fluorescent probes was proposed for the rapid and sensitive detection of the DNMT1 level in this study. Key factors that affect the precision and accuracy of the determination of DNMT1 were optimized. Results Under the optimal conditions, the limit of detection was 0.1 ng/mL, the linear range was 0.1–1,500 ng/mL, the recovery was 91.67%–106.50%, and the relative standard deviations of intra- and inter-assays were respectively 5.45%–11.29% and 7.03%–11.25%. The cross-reactivity rates with DNA methyltransferases 3a and 3b were only 4.0% and 9.4%, respectively. Furthermore, FLISA was successfully used to detect the levels of DNMT1 in human serum samples, and compared with commercial enzyme-linked immunosorbent assay (ELISA) kits. The results revealed that there was a good correlation between FLISA and commercial ELISA kits (correlation coefficient r =0.866, p =0.001). The linear scope of FLISA was broader than ELISA, and the measurement time was much shorter than ELISA kits. Conclusion These indicated that the proposed FLISA method was sensitive and high throughput and can quickly screen the level of DNMT1 in serum samples.
研究领域:
生物技术
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医学诊断
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分子生物学
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癌症研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry C
·
2019
·
IF 4.309
Ali Shmshad,Jialun Tang,Imran Muhammad,Dengbao Han,Xin Zhang,Shuai Chang,Qingfan Shi,Haizheng Zhong
Colloidal quantum dots (QDs) are talented materials and have been extensively investigated in the field of photonics and optoelectronics due to their size-dependent optical properties. The core/shell structure of QDs with a wide band gap shell has been adopted for obtaining stable emission and high photoluminescent (PL) quantum efficiency. However, when employed in active devices such as light-emitting diodes (LEDs), the thick-shell structure of QDs may impede the transportation of carriers, thus deteriorating the device performance. In this work, the effect of the shell thickness of CdSe/ZnS QDs on the device performance is systematically studied through impedance spectroscopy, by constructing the electron-only symmetric device architecture. It is found that the evolution of capacitance in the symmetric device under applied voltage reflects the charge accumulation within the device and predicts the LED performance. The lowest capacitance is evaluated in the symmetric device containing QDs with a medium shell size of 2.1 nm, showing improved performance in the LED with the highest luminance and current efficiency of 26 370 cd/m2 and 8.3 cd/A, respectively.
研究领域:
光子学
·
光电学
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Hao Hao,Meng Liu,Ge Tang,Yi Liu,Feng-Lei Jiang
Thiol ligands are widely used to modify quantum dots (QDs) due to their strong affinity. Aromatic structures can be introduced to improve the charge transport of the QDs. In this work, the as-synthesized CdSe/ZnS core/shell QDs were modified with thiolphenyl (TP) derivatives by ligand exchange. Photoluminescence (PL), ultraviolet–visible (UV–vis) absorption, and time-resolved photoluminescence (TRPL) spectroscopy were used to investigate the optical properties of QDs before and after ligand exchange. The elemental quantification by energy-dispersive X-ray (EDX) spectroscopy proved that TP ligands were adsorbed. The PL intensities of QDs were enhanced after ligand exchange with TP ligands (except for pentafluorothiophenol, PF-TP) through passivation. Besides, the QDs exhibited better stability and electrical conductivity. Combined with 1H nuclear magnetic resonance (1H NMR), fluorescence spectroscopy, and isothermal titration calorimetry (ITC), the effects of electron-donating/-withdrawing ability and steric hindrance of the substituents on the ligand exchanges were analyzed. The reactions of QDs with TP ligands containing electron-donating substituents were exothermic and entropy-decreasing. However, the reactions with those ligands containing electron-withdrawing substituents were exothermic and entropy-increasing. Interestingly, the reaction of PF-TP with QDs could be fitted to a two-stage model. In general, we found that the stronger electron-donating ability of substituent would lead to less desorption of OA ligands, thus fewer trap states, and better passivation, stability, and conductivity of QDs. Good stability and conductivity of QDs are prerequisites for high performance in displays. This work will greatly contribute to the selection of aromatic ligands for QDs.
研究领域:
材料科学
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光学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2024
·Vol. 26
·期 15
·11498-11505
·
IF 2.9
Jiannan Sun,Ke Yan,Aizhao Pan,Pan Zhang,Xuehang Chen,Xinyi Shi,Chengyu Shi
Fluorescence nanothermometry based on quantum dots is a current research hotspot for novel non-contact temperature monitoring, and is of vital significance for the modulation and design of the sensing properties of sensors. Herein, a design strategy to modulate the temperature-sensing characteristics of quantum dots based on the thickness of a shell is proposed. In this study, CdSe/ZnS quantum dot/POSS-based temperature probe films with varying fluorescence characteristics were developed, and the influence of the ZnS shell on temperature sensing was examined by varying the thickness of the ZnS shell. The temperature dependency, linearity, range of applications, and reversibility of quantum dot thin film probes were all considerably regulated by the ZnS shell, according to research on quantum dot/POSS-based films coated with various shell thicknesses. The CdSe/ZnS temperature probe with 4 monolayers (MLs) stood out among the rest due to its strong thermal stability (at least 5 cycles), large usable temperature range (20–80 °C), and excellent temperature sensitivity (R2 > 0.994). The results demonstrated that the temperature sensing performance of quantum dots was the consequence of the combined effect of multiple temperature response properties induced by the thickness of the shell, and the shell control of quantum dots to optimize the temperature sensing performance was an essential approach for the design of temperature probes. This work demonstrates the great potential of the shell in tuning the temperature sensing performance of quantum dots and provides a viable approach for the design of quantum dot temperature probes.
研究领域:
材料科学
·
纳米技术
·
传感器技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）