Journal of the American Chemical Society
·
2025
·
IF 15.6
Shangxin Lin,Chuanzhong Yan,Jie Zhu,Yida Lu,Xiaogang Peng
With CdTe nanocrystals as a model system, we discover a new synthetic strategy for control of size and size distribution of colloidal semiconductor nanocrystals in both nucleation and growth stages. Especially in the nucleation stage, an in situ-formed cadmium complex with approximately one alkanoate and one alkylphosphonate ligand enables both high-yield nucleation by reacting the reactive cadmium-carboxylate bond with Te precursors and efficient size control by immediate passivation with the close-proximity alkylphosphonate ligand from the same complex. Conversely, control on size distribution during either homoepitaxial or heteroepitaxial growth requires reactive cadmium (or zinc) alkanoates as the cationic precursors with a minimum concentration of alkylphosphonate ligands in the novel synergistic solvents. This new strategy not only yields monodisperse CdTe and CdTe/ZnSe core/shell nanocrystals with unprecedented optical quality but also provides a much-needed alternative route for synthesizing monodisperse semiconductor nanocrystals, which is commonly hindered by the growth barrier of the dense ligand monolayer.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2019
·
IF 2.291
Yiling Zhu,Rui Zhu,Jun Xie,Qiuliang Wang,Hu Chen,Yunfei Liu,Yinong Lyu
A novel PS@CdTe multilayers fluorescence microsphere was successfully synthesized by the electrostatic layer-by-layer (LBL) self-assembly technique. The structure, the process of self-assembly and the fluorescence performance were confirmed by high-resolution transmission electron microscope (HRTEM), Zeta potentiometric analyzer and fluorescence spectrophotometer, respectively. The results manifest that when the pH of buffer solution is 7.8, the negative charge on the surface of CdTe quantum dots (QDs) is the largest, which is beneficial to the synthesis of electrostatic self-assembled microspheres. The fluorescence properties of PS@CdTe microspheres increased gradually with the number of layers coated increased, and the optimum number of coating layers is three. Under this condition, the PS@CdTe microspheres exhibited a great increase of 25-fold in fluorescence performance compared to the equal quantity of pure CdTe QDs. Moreover, the emission spectra of PS@CdTe microspheres recorded under the excitation of 410 nm, and shows a strong emission peak located at 524 nm. This kind of core-shell microspheres has a great potential to be used in the field of optoelectronics .
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2022
·
IF 4.132
Jiajia Wang,Xin Hua,Baokang Jin
A facile method for the in situ fabrication of chitosan/polythiophene/CdTe (CS/PTh/CdTe) nanocomposite has been developed. It was then connected with anti-CEA (Ab), which was evoked for the electrochemical detection of carcinoembryonic antigen (CEA, Ag) within K4Fe(CN)6. The results indicate that CS/PTh/CdTe/GCE has a high selectivity for the detection of CEA with a wide linear range of 0.0001–10000 ng/mL and excellent sensitivity with a low detection limit of 40 fg/mL. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), and in situ FT-IR spectra are evoked to study the mechanism of detection of CEA via CS/PTh/CdTe/GCE. The high sensitivity of the electrochemical sensor is due to the fact that the electrochemical oxidation products of K4Fe(CN)6 can directly oxidize CdTe from a low energy state to a high energy state (CdTe)*, making CdTe more prone to be oxidized and facilitate electron transfer. The developed electrochemical biosensor can be used for the detection of real samples, providing a precise method for the detection of CEA with potential application in the clinical detection of tumors.
研究领域:
生物医学工程
·
分析化学
·
肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 31
·25656-25661
·
IF 3.289
Zhixiang Jiang,Katarzyna Matras-Postolek,Ping Yang
Several kinds of hydrophobic quantum dots (QDs) including CdSe, CdTe, CdSe/CdxZn1−xS, and CdTe/CdSe/ZnSe were fabricated via organic synthesis to observe morphology variation during shell coating. CdSe QDs prepared at a relatively high temperature revealed a hexagonal structure and rod morphology. On being coated with a CdxZn1−xS shell, tetrahedron and rod morphologies were observed. It was found that the reaction temperature and injection rate play important roles. The photoluminescence properties of the core/shell QDs depended strongly on their preparation conditions such as temperature and ligands. For CdSe cores created at a relatively low temperature, CdxZn1−xS shell coating resulted in the formation of cubic CdSe/CdxZn1−xS core/shell QDs. This is ascribed to the role of a CdS interlayer. In contrast, multishell CdTe/CdSe/ZnSe QDs revealed a spherical morphology. Furthermore, the self-assembly of QDs with hexagonal structures occurs while regular assembled structures were not observed for QDs with a cubic morphology according to their transmission electron microscopy images. This is ascribed to a dipole force between QDs. This phenomenon is just related to the morphology and crystal structures rather than their composition.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 47
·24612-24618
·
IF 3.708
Yangyang Li,Ben Q. Li
An optical-thermal experimental system, in which CdTe quantum dots (QDs) were used as thermal sensors, is developed for micro-electromechanical system (MEMS) temperature measurements in the high temperature range (>70 °C). Laboratory-prepared CdTe QDs with suitably controlled synthesis conditions show excellent temperature sensitivity. For orange emitting CdTe QDs, calibration from a type A micro-heater yields a linear relation between the spectral peak shift and the temperature over the temperature range of 27 °C to 170 °C, the last being the highest temperature of the heater achieved in our current optical-thermal experimental setup. This linear relation is consistent with the predictions for semiconductor quantum systems from the principle of thermo-quantum mechanics for the temperature above the Debye point. Analysis of the experimental data indicates that the orange emitting QDs possess a thermally-induced spectral-shift sensitivity of 0.34 nm °C−1, which is approximately about 2–3 times better than reported. The excellent repeatability and accuracy of the calibrated orange emitting CdTe QDs as thermal sensors are further demonstrated by applying them in monitoring electric thermal characteristics of type B MEMS structures. While calibration is for up to 170 °C, the temperature of up to 212 °C for the type B MEMS heater was measured with a satisfactory accuracy using the CdTe QDs, further demonstrating the stability of the thermal-spectral properties of the QDs. The existence of a unique “burnout” spectrum in the temperature dependent PL spectra also suggests that optical-thermally sensitive QDs can be applied in both monitoring the temperature development and diagnosing circuit breakout due to over-heating.
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2020
·Vol. 20
·期 9
·5478-5485
·
IF 1.134
Xie Cong,Zhao Yubin,Song Yuxiang,Liu Yingjie,Wang Yaya,Yang Ping
Compared with conventional semiconductor quantum dots, hybrid SiO2 coated CdTe QDs exhibited high stability, long fluorescent lifetime, high photoluminescence quantum yields, and well biocompatibility. In this paper, CdTe QDs with tunable PL from green to red emitting were
prepared by an aqueous synthesis. A sol–gel process resulted in CdTe QDs coated with a hybrid SiO2 shell contained CdS-like clusters to obtain red-shifted PL spectra, increased PL efficiency and high stability. The clusters were formed by the reaction of Cd2+ and
S2− ions generated via the decomposition of thioglycolic acid. The clusters around CdTe cores created a core–shell structure which is very similar with traditional semiconductor core–shell QDs. After being coated with a hybrid SiO2 shell, the PL of green-emitting
naked CdTe QDs was red-shifted largely (~30 nm) while the PL of yellowemitting CdTe QDs revealed a small red-shifted (~20 nm). Furthermore, The PL of red-emitting naked CdTe QDs was red-shifted much small (less than 10 nm). This phenomenon is ascribed to the change of band gap of CdTe cores
with sizes. The red-shift of PL spectra is attributed to the CdS-like clusters around the core rather than the thickness of the hybrid SiO2 shell.
研究领域:
材料科学
·
纳米技术
·
光学
✓ 已验证
DOI
PubMed
高影响因子
LUMINESCENCE
·
2012
·Vol. 28
·期 3
·259-264
·
IF 1.731
Zhonghui Wang,Hongjie Song,Huihui Zhao,Yi Lv
Electrogenerated chemiluminescence (ECL) of thiol-capped CdTe quantum dots (QDs) in aqueous solution was greatly enhanced by PDDA-protected graphene (P-GR) film that were used for the sensitive detection of H 2 O 2 . When the potential was cycled between 0 and −2.3 V, two ECL peaks were observed at −1.1 (ECL-1) and −1.4 V (ECL-2) in pH 11.0, 0.1 M phosphate buffer solution (PBS), respectively. The electron-transfer reaction between individual electrochemically-reduced CdTe nanocrystal species and oxidant coreactants (H 2 O 2 or reduced dissolved oxygen) led to the production of ECL-1. While mass nanocrystals packed densely in the film were reduced electrochemically, assembly of reduced nanocrystal species reacted with coreactants to produce an ECL-2 signal. ECL-1 showed higher sensitivity for the detection of H 2 O 2 concentrations than that of ECL-2. Further, P-GR film not only enhanced ECL intensity of CdTe QDs but also decreased its onset potential. Thus, a novel CdTe QDs ECL sensor was developed for sensing H 2 O 2 . Light intensity was linearly proportional to the concentration of H 2 O 2 between 1.0 × 10 −5 and 2.0 x 10 -7 mol L −1 with a detection limit of 9.8 x 10 −8 mol L −1 . The P-GR thin-film modified glassy carbon electrode (GCE) displayed acceptable reproducibility and long-term stability. Copyright © 2012 John Wiley & Sons, Ltd.
研究领域:
分析化学
·
生物传感
✓ 已验证
DOI
PubMed
高影响因子
BULLETIN OF THE CHEMICAL SOCIETY OF ETHIOPIA
·
2013
·Vol. 27
·期 3
·387-393
·
IF 0.417
Y. Wang,R. Wang,S. Liu,K. Yang,L. Zhou,H. Li
L-Cysteine (Cys)-capped CdTe quantum dots (QDs) were prepared when sodium tellurite worked as a tellurium source and sodium borohydride acted as a reductant. The influences of various experimental variables, including pH values, Cd/Te and Cd/Cys molar ratios, on the photoluminescence (PL) quantum yield (QY) of the obtained CdTe QDs have been systematically investigated. Experimental results indicated that green to red emitting CdTe QDs with maximum quantum yield of 19.4% can be prepared at pH 11.5 and n(Cd2+):n(Te2−):n(Cys) = 1:0.07:2.0. X-Ray powder diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the crystal structure and shape of CdTe QDs. The results showed that the prepared CdTe QDs were of cubic zinc blend crystal structure in a sphere-like shape. KEY WORDS: Semicondutor nanocrystal, Chemical synthesis, Optical properties, Luminescence Bull. Chem. Soc. Ethiop. 2013, 27(3), 387-393.DOI: http://dx.doi.org/10.4314/bcse.v27i3.7
研究领域:
材料科学
·
化学合成
·
光学性质
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Yuxin Liu,Feixue Gao,Shuya Liu,Hangxi Liu,Ming Fang,Xiaoli Tan
The utilization of near-infrared (NIR) light may greatly enlarge the application range of irradiated light of a photocatalyst, which is still an issue needing to be solved. In this work, CdTe nanoparticles are firstly found to be endowed with the capacity to photo-reduce Cr(VI) to Cr(III) under infrared light irradiation. The CdTe nanoparticles are prepared under a facile hydrothermal condition, with diameters of approximately 22 nm, which shows high photo-reduced efficiencies to Cr(VI) of 82.44% at the irradiation of a Xe lamp (500 W, including the visible light and infrared light), and 25.54% under the irradiation of infrared light, respectively. The active species of e − , h + , and OH participate in the reduction of Cr(VI), and the photogenerated e − and OH both play a critical role in the infrared light region. This study proposes a new pathway for Cr(VI) photoreduction in wastewater under visible-NIR light irradiation which shows an application potential as a photocatalyst at the infrared light range and provides new insights for pollution reduction and environmental improvement.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2016
·Vol. 16
·期 9
·9806-9812
·
IF 1.338
Miao Yanping,Zhao Jie,He Haiyan,Du Yingying,Liu Yunshi,Yang Ping
Hybrid SiO2 coated CdTe quantum dots (QDs) consisted of a CdTe core and a hybrid shell with CdS-like clusters inside were created via a two-step synthesis including a sol–gel route and a reflux process. Being coated with the hybrid SiO2 shell, the photoluminescence
(PL) color of the QDs was red-shifted to yellow from green and their PL efficiency increased remarkably. Graphene oxide (GO) nanosheets are obtained through modified hummers’ method. The attachment of the QDs was carried out through the covalent bond between the hybrid SiO2
shell and the oxygen-containing groups on the surface of GO. The GO was reduced into graphene in the reflux. The hybrid SiO2 coated CdTe QDs were quenched after grafted on the graphene. The photoelectrochemical performance of graphene-QD composites modified electrode has noteworthy
change after it is immersed in Cu2+ ion solution, because the sedimentation equilibrium constant of CuS is much lower than that of CdS. Graphene-hybrid SiO2 coated CdTe QDs composites is less toxic, it opens up an application possibility for ion detection.
研究领域:
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
Journal of Nanomaterials
·
2017
·
IF 1.871
Lei Du,Zhejun Liu,Suhua Jiang
We demonstrated the inkjet-printed CdTe quantum dots-polyurethane acrylate thin films and their potential application in the display devices. The water soluble CdTe QDs were synthesized through the wet chemistry and the emission wavelengths can be freely tuned during the preparation process. Combining with the UV curable resin polyurethane acrylate, the QDs inks were prepared and the influence of diluent and water content on the performance of resultant films was studied. The tensile stress of the films cured from the QDs inks with diluent increased from 10.6 MPa to 27.5 MPa and the low water content led to uniform polymer matrix. Furthermore, the existence of diluent and low water content would all improve the fluorescence stability of the thin films. Finally, the thin films can be deposited on different substrates and well controlled to meet the RGB color standard, which will pave the way to a simple, low-cost, large-scale, and highly reliable method for the application of flexible displays.
研究领域:
材料科学
·
显示技术
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 129
·106599-106606
·
IF 3.84
Hucheng Zhang,Huili Wang,Kelu Du,Xinxin Ma,Jianji Wang
Assembling ultra-small nanoparticles into nanosized colloidal nanocrystal clusters (CNCs) to create novel collective properties still poses tremendous challenges. This work reports the fabrication of photoluminescent CdTe CNCs on the nanoscale and their thermo-responsive properties. Diblock copolymers of poly(N-(2-aminoethyl) acrylamide-b-N-isopropylacrylamide) (PNAEAM-b-PNIPAM) were synthesized and employed as self-assembling actuators of CNCs. The side chains of PNAEAM blocks act as efficient anchors to capture CdTe nanocrystals via surface ligand identification. The thermo-sensitive PNIPAM blocks serve as the protection layer of CNCs and the trigger to turn off/on the photoluminescence CNCs during heating/cooling cycles. The [HS–C10mim]+ ligands with smart noncovalent interactions on the as-prepared nanocrystals render the CNCs rapid and reversible thermo-response performances. These make the CNCs an excellent thermo-responser, and offer a new controllable self-assembly route for designing and engineering multifunctional nanosized CNCs.
研究领域:
材料科学
·
纳米技术
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）