151
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Affiliation(s)
- Liheng Wu
- Department
of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Adriana Mendoza-Garcia
- Department
of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Qing Li
- Department
of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Shouheng Sun
- Department
of Chemistry, Brown University, Providence, Rhode Island 02912, United States
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152
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Pu C, Peng X. To Battle Surface Traps on CdSe/CdS Core/Shell Nanocrystals: Shell Isolation versus Surface Treatment. J Am Chem Soc 2016; 138:8134-42. [PMID: 27312799 DOI: 10.1021/jacs.6b02909] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Electronic traps at the inorganic-organic interface of colloidal quantum dots (QDs) are detrimental to their luminescent properties. Several types of interface traps were identified for single-crystalline CdSe/CdS core/shell QDs, which were all found to be extrinsic to either the core/shell structure or their optical performance. The electron traps-presumably excess or unpassivated Cd surface sites-are shallow ones and could be readily isolated from the electron wave function of the excitons with more than ∼2 monolayers of CdS shell. There were two identifiable deep hole traps within the bandgap of the QDs, i.e., the surface adsorbed H2S and unpassivated surface S sites. The surface adsorbed H2S could be removed by either degassing processes or photochemical decomposition of H2S without damaging the QDs. The unpassivated surface S sites could be removed by surface treatment with cadmium carboxylates. Understanding of the surface traps enabled establishment of new phosphine-free synthetic schemes for either single-precursor or successive-ion-layer-adsorption-and-reaction approach, which yielded CdSe/CdS core/shell QDs with near-unity photoluminescence quantum yield and monoexponential photoluminescence decay dynamics with 2-10 monolayers of CdS shell.
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Affiliation(s)
- Chaodan Pu
- Center for Chemistry of Novel & High-Performance Materials, Department of Chemistry, Zhejiang University , Hangzhou, 310027, P. R. China
| | - Xiaogang Peng
- Center for Chemistry of Novel & High-Performance Materials, Department of Chemistry, Zhejiang University , Hangzhou, 310027, P. R. China
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153
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Walsh BR, Saari JI, Krause MM, Nick R, Coe-Sullivan S, Kambhampati P. Surface and interface effects on non-radiative exciton recombination and relaxation dynamics in CdSe/Cd,Zn,S nanocrystals. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2015.11.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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154
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155
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Kotresh MG, Adarsh KS, Shivkumar MA, Inamdar SR. Steady State and Time Resolved Spectroscopic Study of CdSe and CdSe/ZnS QDs:FRET Approach. J Fluoresc 2016; 26:1249-59. [DOI: 10.1007/s10895-016-1812-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 04/26/2016] [Indexed: 02/03/2023]
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156
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Moon JS, Liang Y, Kim I, Oh JW, Winiarz JG. Formation of water soluble wavelength tunable InGaP and InP quantum dots. Polym Bull (Berl) 2016. [DOI: 10.1007/s00289-016-1674-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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157
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Ghosh S, Saha M, Ashok VD, Chatterjee A, De SK. Excitation dependent multicolor emission and photoconductivity of Mn, Cu doped In2S3 monodisperse quantum dots. NANOTECHNOLOGY 2016; 27:155708. [PMID: 26934114 DOI: 10.1088/0957-4484/27/15/155708] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Indium sulphide (In2S3) quantum dots (QDs) of average size 6 ± 2 nm and hexagonal nanoplatelets of average size 37 ± 4 nm have been synthesized from indium myristate and indium diethyl dithiocarbamate precursors respectively. The absorbance and emission band was tuned with variation of nanocrytal size from very small in the strong confinement regime to very large in the weak confinement regime. The blue emission and its shifting with size has been explained with the donor-acceptor recombination process. The 3d element doping (Mn(2+) and Cu(2+)) is found to be effective for formation of new emission bands at higher wavelengths. The characteristic peaks of Mn(2+) and Cu(2+) and the modification of In(3+) peaks in the x-ray photoelectric spectrum (XPS) confirm the incorporation of Mn(2+) and Cu(2+) into the In2S3 matrix. The simulation of the electron paramagnetic resonance signal indicates the coexistence of isotropic and axial symmetry for In and S vacancies. Moreover, the majority of Mn(2+) ions and sulphur vacancies (VS ) reside on the surface of nanocrystals. The quantum confinement effect leads to an enhancement of band gap up to 3.65 eV in QDs. The formation of Mn 3d levels between conduction band edge and shallow donor states is evidenced from a systematic variation of emission spectra with the excitation wavelength. In2S3 QDs have been established as efficient sensitizers to Mn and Cu emission centers. Fast and slow components of photoluminescence (PL) decay dynamics in Mn and Cu doped QDs are interpreted in terms of surface and bulk recombination processes. Fast and stable photodetctors with high photocurrent gain are fabricated with Mn and Cu doped QDs and are found to be faster than pure In2S3. The fastest response time in Cu doped QDs is an indication of the most suitable system for photodetector devices.
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Affiliation(s)
- Sirshendu Ghosh
- Department of Materials Science, Indian Association for the Cultivation of Science, Kolkata-700032, India
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158
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Boken J, Soni SK, Kumar D. Microfluidic Synthesis of Nanoparticles and their Biosensing Applications. Crit Rev Anal Chem 2016; 46:538-61. [DOI: 10.1080/10408347.2016.1169912] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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159
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Shahdost-Fard F, Roushani M. Conformation switching of an aptamer based on cocaine enhancement on a surface of modified GCE. Talanta 2016; 154:7-14. [PMID: 27154642 DOI: 10.1016/j.talanta.2016.03.055] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 03/16/2016] [Accepted: 03/16/2016] [Indexed: 01/10/2023]
Abstract
An ultrasensitive aptasensor was fabricated as an electrochemical nanotool based on the conformation switching of an aptamer (Apt). The Apt which was covalently attached on the surface of a glassy carbon electrode (GCE) covered with cadmium telluride (CdTe) quantum dots (QDs) works as a unique modifier for assaying cocaine. The Apt was combined with cocaine to form a three-way junction complex; this complex increased the steric hindrance of the modified GCE surface and resulted in a variation of the corresponding current of a redox probe. In the present study, DPV technique for cocaine detection was applied and resulted in an unprecedented detection limit (LOD) of 5.0±0.1pmolL(-1), which is more sensitive than previously reported methods. One of the greatest advantages of this aptasensor is the elimination of enzymes or antibodies. It is also relatively a highly sensitive, simple, reproducible, and controllable nanotool. Likewise, it can be easily miniaturized, which is a necessary condition for the high-throughput system and on-site applications. The offered nanotool has a great promise for the routine analysis of the ultra-trace amounts of cocaine, which is important for law enforcement and clinical medicine. It is notable to say that further attempts are under way in our laboratory for the construction of other aptasensors with higher performance for specific targets such as the detection of methadone (MTD) and ibuprofen (IBP).
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160
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Jung J, Lin CH, Yoon YJ, Malak ST, Zhai Y, Thomas EL, Vardeny V, Tsukruk VV, Lin Z. Crafting Core/Graded Shell-Shell Quantum Dots with Suppressed Re-absorption and Tunable Stokes Shift as High Optical Gain Materials. Angew Chem Int Ed Engl 2016; 55:5071-5. [DOI: 10.1002/anie.201601198] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Jaehan Jung
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Chun Hao Lin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Young Jun Yoon
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Sidney T. Malak
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Yaxin Zhai
- Department of Physics and Astronomy; University of Utah; Salt Lake City UT 84112 USA
| | - Edwin L. Thomas
- Department of Materials Science and Nanoengineering; Rice University; Houston TX 77251 USA
| | - Valy Vardeny
- Department of Physics and Astronomy; University of Utah; Salt Lake City UT 84112 USA
| | - Vladimir V. Tsukruk
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Zhiqun Lin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
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161
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Jung J, Lin CH, Yoon YJ, Malak ST, Zhai Y, Thomas EL, Vardeny V, Tsukruk VV, Lin Z. Crafting Core/Graded Shell-Shell Quantum Dots with Suppressed Re-absorption and Tunable Stokes Shift as High Optical Gain Materials. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601198] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jaehan Jung
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Chun Hao Lin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Young Jun Yoon
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Sidney T. Malak
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Yaxin Zhai
- Department of Physics and Astronomy; University of Utah; Salt Lake City UT 84112 USA
| | - Edwin L. Thomas
- Department of Materials Science and Nanoengineering; Rice University; Houston TX 77251 USA
| | - Valy Vardeny
- Department of Physics and Astronomy; University of Utah; Salt Lake City UT 84112 USA
| | - Vladimir V. Tsukruk
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Zhiqun Lin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
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162
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Son JG, Choi E, Piao Y, Han SW, Lee TG. Probing organic ligands and their binding schemes on nanocrystals by mass spectrometric and FT-IR spectroscopic imaging. NANOSCALE 2016; 8:4573-4578. [PMID: 26842618 DOI: 10.1039/c5nr07592k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report an analysis method to identify conjugated ligands and their binding states on semiconductor nanocrystals based on their molecular information. Surface science techniques, such as time-of-flight secondary-ion mass spectrometry (ToF-SIMS) and FT-IR spectroscopy, are adopted based on the micro-aggregated sampling method. Typical trioctylphosphine oxide-based synthesis methods of CdSe/ZnS quantum dots (QDs) have been criticized because of the peculiar effects of impurities on the synthesis processes. Because the ToF-SIMS technique provides molecular composition evidence on the existence of certain ligands, we were able to clearly identify n-octylphosphonic acid (OPA) as a surface ligand on CdSe/ZnS QDs. Furthermore, the complementary use of the ToF-SIMS technique with the FT-IR technique could reveal the OPA ligands' binding state as bidentate complexes.
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Affiliation(s)
- Jin Gyeong Son
- Department of Chemistry and KI for the NanoCentury, KAIST, Daejeon 34141, Korea. and Center for Nano-Bio Measurement, Korea Research Institute of Standard and Science, Daejeon 34113, Korea.
| | - Eunjin Choi
- Program in Nano Science and Technology, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 08826, Korea and Advanced Institute of Convergence Technology, Suwon 16227, Korea
| | - Yuanzhe Piao
- Program in Nano Science and Technology, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 08826, Korea and Advanced Institute of Convergence Technology, Suwon 16227, Korea
| | - Sang Woo Han
- Department of Chemistry and KI for the NanoCentury, KAIST, Daejeon 34141, Korea.
| | - Tae Geol Lee
- Center for Nano-Bio Measurement, Korea Research Institute of Standard and Science, Daejeon 34113, Korea.
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163
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Swart I, Liljeroth P, Vanmaekelbergh D. Scanning probe microscopy and spectroscopy of colloidal semiconductor nanocrystals and assembled structures. Chem Rev 2016; 116:11181-219. [PMID: 26900754 DOI: 10.1021/acs.chemrev.5b00678] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Colloidal semiconductor nanocrystals become increasingly important in materials science and technology, due to their optoelectronic properties that are tunable by size. The measurement and understanding of their energy levels is key to scientific and technological progress. Here we review how the confined electronic orbitals and related energy levels of individual semiconductor quantum dots have been measured by means of scanning tunneling microscopy and spectroscopy. These techniques were originally developed for flat conducting surfaces, but they have been adapted to investigate the atomic and electronic structure of semiconductor quantum dots. We compare the results obtained on colloidal quantum dots with those on comparable solid-state ones. We also compare the results obtained with scanning tunneling spectroscopy with those of optical spectroscopy. The first three sections provide an introduction to colloidal quantum dots, and a theoretical basis to be able to understand tunneling spectroscopy on dots attached to a conducting surface. In sections 4 and 5 , we review the work performed on lead-chalcogenide nanocrystals and on colloidal quantum dots and rods of II-VI compounds, respectively. In section 6 , we deal with colloidal III-V nanocrystals and compare the results with their self-assembled counter parts. In section 7 , we review the work on other types of semiconductor quantum dots, especially on Si and Ge nanocrystals.
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Affiliation(s)
- Ingmar Swart
- Debye Institute for Nanomaterials Science, Chemistry Department, University of Utrecht , Princetonplein 5, 3584 CC Utrecht, The Netherlands
| | - Peter Liljeroth
- Department of Applied Physics, Aalto University School of Science , PO Box 15100, 00076 Aalto, Finland
| | - Daniel Vanmaekelbergh
- Debye Institute for Nanomaterials Science, Chemistry Department, University of Utrecht , Princetonplein 5, 3584 CC Utrecht, The Netherlands
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164
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Qi T, Yang HQ, Whitfield DM, Yu K, Hu CW. Insights into the Mechanistic Role of Diphenylphosphine Selenide, Diphenylphosphine, and Primary Amines in the Formation of CdSe Monomers. J Phys Chem A 2016; 120:918-31. [PMID: 26745558 DOI: 10.1021/acs.jpca.5b10675] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The formation mechanism of CdSe monomers from the reaction of cadmium oleate (Cd(OA)2) and SePPh2H in the presence of HPPh2 and RNH2 was studied systematically at the M06//B3LYP/6-31++G(d,p),SDD level in 1-octadecene solution. Herein, SePPh2H, HPPh2, and RNH2 act as hydrogen/proton donors with a decreased capacity, leading to the release of oleic acid (RCOOH). The longer the radius of the coordinated atom is, the larger the size of the cyclic transition state is, which lowers the activation strain and the Gibbs free energy of activation for the release of RCOOH. From the resulting RCOOCdSe-PPh2, for the formation of Ph2P-CdSe-PPh2 (G), SePPh2H acts as a catalyst, in which the turnover frequency determining transition state (TDTS) is characteristic of the Se-P bond cleavage. For the formation of RHN-CdSe-PPh2 (H), SePPh2H also serves as a catalyst, in which the TDTS is representative of the N-H bond cleavage. For the formation of Ph2PSe-CdSe-NHR (I), HPPh2 behaves as a catalyst, in which the TDTS is typical of the Se-P and N-H bond cleavage. The rate constants increase as kI < kH < kG, which is in good agreement with our previous experimental observations reported. The present study brings insight into the use of additives such as HPPh2 and RNH2 to synthesize colloidal quantum dots.
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Affiliation(s)
- Ting Qi
- College of Chemical Engineering, ‡Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, and §College of Physics, Sichuan University , Chengdu, Sichuan 610064, People's Republic of China
| | - Hua-Qing Yang
- College of Chemical Engineering, ‡Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, and §College of Physics, Sichuan University , Chengdu, Sichuan 610064, People's Republic of China
| | - Dennis M Whitfield
- College of Chemical Engineering, ‡Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, and §College of Physics, Sichuan University , Chengdu, Sichuan 610064, People's Republic of China
| | - Kui Yu
- College of Chemical Engineering, ‡Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, and §College of Physics, Sichuan University , Chengdu, Sichuan 610064, People's Republic of China
| | - Chang-Wei Hu
- College of Chemical Engineering, ‡Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, and §College of Physics, Sichuan University , Chengdu, Sichuan 610064, People's Republic of China
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165
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Taniguchi S, Sandiford L, Cooper M, Rosca EV, Ahmad Khanbeigi R, Fairclough SM, Thanou M, Dailey LA, Wohlleben W, von Vacano B, de Rosales RTM, Dobson PJ, Owen DM, Green M. Hydrophobin-Encapsulated Quantum Dots. ACS APPLIED MATERIALS & INTERFACES 2016; 8:4887-4893. [PMID: 26824334 DOI: 10.1021/acsami.5b11354] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The phase transfer of quantum dots to water is an important aspect of preparing nanomaterials that are suitable for biological applications, and although numerous reports describe ligand exchange, very few describe efficient ligand encapsulation techniques. In this report, we not only report a new method of phase transferring quantum dots (QDs) using an amphiphilic protein (hydrophobin) but also describe the advantages of using a biological molecule with available functional groups and their use in imaging cancer cells in vivo and other imaging applications.
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Affiliation(s)
- Shohei Taniguchi
- Department of Physics, King's College London , Strand, London WC2R 2LS, United Kingdom
| | - Lydia Sandiford
- Department of Imaging Chemistry and Biology, Division of Imaging Science and Biomedical Engineering, King's College London , Fourth Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Maggie Cooper
- Department of Imaging Chemistry and Biology, Division of Imaging Science and Biomedical Engineering, King's College London , Fourth Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Elena V Rosca
- Institute of Pharmaceutical Science, King's College London , Fifth Floor, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, United Kingdom
| | - Raha Ahmad Khanbeigi
- Institute of Pharmaceutical Science, King's College London , Fifth Floor, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, United Kingdom
| | - Simon M Fairclough
- Department of Physics, King's College London , Strand, London WC2R 2LS, United Kingdom
| | - Maya Thanou
- Institute of Pharmaceutical Science, King's College London , Fifth Floor, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, United Kingdom
| | - Lea Ann Dailey
- Institute of Pharmaceutical Science, King's College London , Fifth Floor, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, United Kingdom
| | - Wendel Wohlleben
- Material Physics Research, BASF SE , 67056 Ludwigshafen, Germany
| | | | - Rafael T M de Rosales
- Department of Imaging Chemistry and Biology, Division of Imaging Science and Biomedical Engineering, King's College London , Fourth Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Peter J Dobson
- Warwick Manufacturing Group, International Manufacturing Centre, University of Warwick , Coventry, CV4 7AL, United Kingdom
| | - Dylan M Owen
- Department of Physics, King's College London , Strand, London WC2R 2LS, United Kingdom
| | - Mark Green
- Department of Physics, King's College London , Strand, London WC2R 2LS, United Kingdom
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166
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Lee DU, Kim DH, Choi DH, Kim SW, Lee HS, Yoo KH, Kim TW. Microstructural and optical properties of CdSe/CdS/ZnS core-shell-shell quantum dots. OPTICS EXPRESS 2016; 24:A350-A357. [PMID: 26832587 DOI: 10.1364/oe.24.00a350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
CdSe/CdS/ZnS core-shell-shell quantum dots (QDs) were synthesized by using a solution process. High-resolution transmission electron microscopy images and energy dispersive spectroscopy profiles confirmed that stoichiometric CdSe/CdS/ZnS core-shell-shell QDs were formed. Ultraviolet-visible absorption and photoluminescence (PL) spectra of CdSe/CdS/ZnS core-shell-shell QDs showed the dominant excitonic transitions from the ground electronic subband to the ground hole subband (1S(e)-1S(3/2)(h)). The PL mechanism is suggested; the carriers generated by the exciting high-energy photons in the shell region are relaxed to the band-edge states of the core region and recombined to emit lower-energy photons. The activation energy of the carriers confined in the CdSe/CdS/ZnS core-shell-shell QDs, as obtained from temperature-dependent PL spectra, was 200 meV. The quantum efficiency of the CdSe/CdS/ZnS core-shell-shell QDs at 300 K was estimated to be approximately 57%.
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167
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Ghosh AB, Saha N, Sarkar A, Dutta AK, Biswas P, Nag K, Adhikary B. Morphological tuning of Eu2O2S nanoparticles, manifestation of peroxidase-like activity and glucose assay use. NEW J CHEM 2016. [DOI: 10.1039/c5nj02705e] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We present a single source precursor driven synthesis of Eu2O2S with variable shapes, which effectively mimic peroxidase activity, and were successfully employed to selectively detect and determine glucose.
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Affiliation(s)
- Abhisek Brata Ghosh
- Department of Chemistry
- Indian Institute of Engineering Science and Technology
- Howrah 711 103
- India
| | - Namrata Saha
- Department of Chemistry
- Indian Institute of Engineering Science and Technology
- Howrah 711 103
- India
| | - Arpita Sarkar
- Department of Chemistry
- Indian Institute of Engineering Science and Technology
- Howrah 711 103
- India
| | - Amit Kumar Dutta
- Department of Chemistry
- Indian Institute of Engineering Science and Technology
- Howrah 711 103
- India
| | - Papu Biswas
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Kamalaksha Nag
- Department of Inorganic Chemistry
- Indian Association for the Cultivation of Science
- Kolkata 700032
- India
| | - Bibhutosh Adhikary
- Department of Chemistry
- Indian Institute of Engineering Science and Technology
- Howrah 711 103
- India
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168
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Sadhanala HK, Senapati S, Nanda KK. Understanding of nitrogen-doped carbon nanoparticles based solid phosphors for white light emitting diodes. RSC Adv 2016. [DOI: 10.1039/c6ra11208k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Filter coffee powder derived nitrogen-doped carbon nanoparticles (N-CNPs) for white light emitting diodes.
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Affiliation(s)
| | - Subrata Senapati
- Materials Research Centre
- Indian Institute of Science
- Bangalore-560012
- India
| | - K. K. Nanda
- Materials Research Centre
- Indian Institute of Science
- Bangalore-560012
- India
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169
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Yan Y, Tian J, Hu F, Wang X, Shen Z. A near IR photosensitizer based on self-assembled CdSe quantum dot-aza-BODIPY conjugate coated with poly(ethylene glycol) and folic acid for concurrent fluorescence imaging and photodynamic therapy. RSC Adv 2016. [DOI: 10.1039/c6ra23113f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Nanocomposite comprised of CdSe quantum dot-thiophene-substituted aza-BODIPY conjugate coated with FA and PEG has been developed for simultaneous fluorescence imaging and photodynamic therapy of HeLa cells via Förster resonance energy transfer.
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Affiliation(s)
- Yu Yan
- State Key Laboratory of Coordination Chemistry
- Collaborative Innovation Center of Advanced Microstructures
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210046
| | - Jiangwei Tian
- State Key Laboratory of Natural Medicines
- Jiangsu Key Laboratory of TCM Evaluation and Translational Research
- Department of Complex Prescription of TCM
- China Pharmaceutical University
- Nanjing 211198
| | - Fengrui Hu
- Laboratory of Micro/Nano-photonics and Ultrafast Spectroscopy
- School of Physics
- Nanjing University
- Nanjing 210093
- China
| | - Xiaoyong Wang
- Laboratory of Micro/Nano-photonics and Ultrafast Spectroscopy
- School of Physics
- Nanjing University
- Nanjing 210093
- China
| | - Zhen Shen
- State Key Laboratory of Coordination Chemistry
- Collaborative Innovation Center of Advanced Microstructures
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210046
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170
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Aguilera-Sigalat J, Bradshaw D. Synthesis and applications of metal-organic framework–quantum dot (QD@MOF) composites. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2015.08.004] [Citation(s) in RCA: 194] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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171
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Abstract
Photoactive nanoparticles are smart systems that exhibit unique optical properties. In general, their intrinsic properties are size dependent. The degree and type of response to size are both related to their composition. Nanoparticles usually require to be capped with organic ligands in order to be dispersible in an aqueous or organic media, thus leading to nanoparticle colloidal dispersions and enhancing the processability of the material. The organic ligand also plays a key role in their preparation. In addition, the high surface-to-volume ratio of the nanoparticles combined with the affinity of the ligands for the nanoparticle surface can be used to place a large number of functional molecules at their periphery. The purpose of this chapter is to understand the synergism between nanoparticles and organic ligands with regard to their preparation, performance, and applicability.
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172
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Zimdars J, Bredol M. On the influence of coordinating solvents on the reduction of selenium for the phosphine-free synthesis of metal selenide nanoparticles. NEW J CHEM 2016. [DOI: 10.1039/c5nj02676h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The bifunctionality of a coordinating solvent (oleylamine) plays an important role in the dissolution step of selenium during the nanoparticle synthesis.
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Affiliation(s)
- Julia Zimdars
- Münster University of Applied Sciences
- Department of Chemical Engineering
- 48565 Steinfurt
- Germany
| | - Michael Bredol
- Münster University of Applied Sciences
- Department of Chemical Engineering
- 48565 Steinfurt
- Germany
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173
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Zha C, Ji C, Zhang J, Shen L, Zhang X, Dong S, Bao N. Facet engineering of monodisperse PbS nanocrystals with shape- and facet-dependent photoresponse activity. RSC Adv 2016. [DOI: 10.1039/c6ra24119k] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Monodisperse PbS nanocrystals with three different shapes for designing optoelectronic devices.
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Affiliation(s)
- Chenyang Zha
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
| | - Cheng Ji
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
| | - Junjie Zhang
- Department of Physics
- Southeast University
- Nanjing
- P. R. China
| | - Liming Shen
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
| | - Xiaoyan Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
| | - Shuai Dong
- Department of Physics
- Southeast University
- Nanjing
- P. R. China
| | - Ningzhong Bao
- State Key Laboratory of Materials-Oriented Chemical Engineering
- College of Chemical Engineering
- Nanjing Tech University
- Nanjing
- P. R. China
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174
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Zhan N, Palui G, Kapur A, Palomo V, Dawson PE, Mattoussi H. Controlling the Architecture, Coordination, and Reactivity of Nanoparticle Coating Utilizing an Amino Acid Central Scaffold. J Am Chem Soc 2015; 137:16084-97. [DOI: 10.1021/jacs.5b10359] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Naiqian Zhan
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Goutam Palui
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Anshika Kapur
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Valle Palomo
- Department
of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Philip E. Dawson
- Department
of Chemistry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Hedi Mattoussi
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
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175
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Rinkel T, Raj AN, Dühnen S, Haase M. Synthese aufwärtskonvertierender 10 nm großer β-NaYF4
:Yb,Er/NaYF4
-Kern/Schale-Nanokristalle mit 5 nm großen Partikelkernen. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201508838] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Thorben Rinkel
- Institut für Chemie neuer Materialien; Universität Osnabrück; Barbarastraße 7 49076 Osnabrück Deutschland
| | - Athira Naduviledathu Raj
- Institut für Chemie neuer Materialien; Universität Osnabrück; Barbarastraße 7 49076 Osnabrück Deutschland
| | - Simon Dühnen
- Institut für Chemie neuer Materialien; Universität Osnabrück; Barbarastraße 7 49076 Osnabrück Deutschland
| | - Markus Haase
- Institut für Chemie neuer Materialien; Universität Osnabrück; Barbarastraße 7 49076 Osnabrück Deutschland
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176
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Rinkel T, Raj AN, Dühnen S, Haase M. Synthesis of 10 nm β-NaYF4
:Yb,Er/NaYF4
Core/Shell Upconversion Nanocrystals with 5 nm Particle Cores. Angew Chem Int Ed Engl 2015; 55:1164-7. [DOI: 10.1002/anie.201508838] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 10/20/2015] [Indexed: 01/30/2023]
Affiliation(s)
- Thorben Rinkel
- Institute of Chemistry of New Materials; University of Osnabrück; Barbarastrasse 7 49076 Osnabrück Germany
| | - Athira Naduviledathu Raj
- Institute of Chemistry of New Materials; University of Osnabrück; Barbarastrasse 7 49076 Osnabrück Germany
| | - Simon Dühnen
- Institute of Chemistry of New Materials; University of Osnabrück; Barbarastrasse 7 49076 Osnabrück Germany
| | - Markus Haase
- Institute of Chemistry of New Materials; University of Osnabrück; Barbarastrasse 7 49076 Osnabrück Germany
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177
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Krause MM, Jethi L, Mack TG, Kambhampati P. Ligand Surface Chemistry Dictates Light Emission from Nanocrystals. J Phys Chem Lett 2015; 6:4292-4296. [PMID: 26538044 DOI: 10.1021/acs.jpclett.5b02015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
There are several contradictory accounts of the changes to the emissive behavior of semiconductor nanocrystal upon a ligand exchange from trioctylphosphine/cadmium-phosphonates passivation to N-butylamine. This communication explains the contradictory accounts of this reaction using new insights into ligand chemistry. Also, a previously unknown link between surface emission and cadmium-phosphonate (Z-type) ligands is shown.
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Affiliation(s)
- Michael M Krause
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Lakshay Jethi
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Timothy G Mack
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Patanjali Kambhampati
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
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178
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Wang W, Ji X, Kapur A, Zhang C, Mattoussi H. A multifunctional polymer combining the imidazole and zwitterion motifs as a biocompatible compact coating for quantum dots. J Am Chem Soc 2015; 137:14158-72. [PMID: 26465679 DOI: 10.1021/jacs.5b08915] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We introduce a set of multicoordinating imidazole- and zwitterion-based ligands suited for surface functionalization of quantum dots (QDs). The polymeric ligands are built using a one-step nucleophilic addition reaction between poly(isobutylene-alt-maleic anhydride) and distinct amine-containing functionalities. This has allowed us to introduce several imidazole anchoring groups along the polymer chain for tight coordination to the QD surface and a controllable number of zwitterion moieties for water solubilization. It has also permitted the introduction of reactive and biomolecular groups for further conjugation and targeting. The QDs capped with these new ligands exhibit excellent long-term colloidal stability over a broad range of pH, toward excess electrolyte, in cell-growth media, and in the presence of natural reducing agents such as glutathione. These QDs are also resistant to the oxidizing agent H2O2. More importantly, by the use of zwitterion moieties as the hydrophilic block, this polymer design provides QDs with a thin coating and compact overall dimensions. These QDs are easily self-assembled with full size proteins expressed with a polyhistidine tag via metal-histidine coordination. Additionally, the incorporation of amine groups allows covalent coupling of the QDs to the neurotransmitter dopamine. This yields redox-active QD platforms that can be used to track pH changes and detect Fe ions and cysteine through charge-transfer interactions. Finally, we found that QDs cap-exchanged with folic acid-functionalized ligands could effectively target cancer cells, where folate-receptor-mediated endocytosis of QDs into living cells was time- and concentration-dependent.
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Affiliation(s)
- Wentao Wang
- Department of Chemistry and Biochemistry, Florida State University , 95 Chieftan Way, Tallahassee, Florida 32306, United States
| | - Xin Ji
- Department of Chemistry and Biochemistry, Florida State University , 95 Chieftan Way, Tallahassee, Florida 32306, United States
| | - Anshika Kapur
- Department of Chemistry and Biochemistry, Florida State University , 95 Chieftan Way, Tallahassee, Florida 32306, United States
| | - Chengqi Zhang
- Department of Chemistry and Biochemistry, Florida State University , 95 Chieftan Way, Tallahassee, Florida 32306, United States
| | - Hedi Mattoussi
- Department of Chemistry and Biochemistry, Florida State University , 95 Chieftan Way, Tallahassee, Florida 32306, United States
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179
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Gollner C, Ziegler J, Protesescu L, Dirin DN, Lechner RT, Fritz-Popovski G, Sytnyk M, Yakunin S, Rotter S, Yousefi Amin AA, Vidal C, Hrelescu C, Klar TA, Kovalenko MV, Heiss W. Random Lasing with Systematic Threshold Behavior in Films of CdSe/CdS Core/Thick-Shell Colloidal Quantum Dots. ACS NANO 2015; 9:9792-801. [PMID: 26364796 DOI: 10.1021/acsnano.5b02739] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
While over the past years the syntheses of colloidal quantum dots (CQDs) with core/shell structures were continuously improved to obtain highly efficient emission, it has remained a challenge to use them as active materials in laser devices. Here, we report random lasing at room temperature in films of CdSe/CdS CQDs with different core/shell band alignments and extra thick shells. Even though the lasing process is based on random scattering, we find systematic dependencies of the laser thresholds on morphology and laser spot size. To minimize laser thresholds, optimizing the film-forming properties of the CQDs, proven by small-angle X-ray scattering, was found to be more important than the optical parameters of the CQDs, such as biexciton lifetime and binding energy or fluorescence decay time. Furthermore, the observed systematic behavior turned out to be highly reproducible after storing the samples in air for more than 1 year. These highly reproducible systematic dependencies suggest that random lasing experiments are a valuable tool for testing nanocrystal materials, providing a direct and simple feedback for further development of colloidal gain materials toward lasing in continuous wave operation.
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Affiliation(s)
| | | | - Loredana Protesescu
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland
- Empa - Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Dmitry N Dirin
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland
- Empa - Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Rainer T Lechner
- Institut für Physik, Montanuniversität Leoben , Franz-Josef-Strasse 18, A-8700 Leoben, Austria
| | - Gerhard Fritz-Popovski
- Institut für Physik, Montanuniversität Leoben , Franz-Josef-Strasse 18, A-8700 Leoben, Austria
| | | | - Sergii Yakunin
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland
- Empa - Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Stefan Rotter
- Institute for Theoretical Physics, Vienna University of Technology , Wiedner Hauptstraße 8-10/136, 1040 Vienna, Austria
| | - Amir Abbas Yousefi Amin
- Materials for Electronics and Energy Technology (i-MEET), Friedrich-Alexander-Universität Erlangen-Nürnberg , Martensstraße 7, 91058 Erlangen, Germany
- Energie Campus Nürnberg (EnCN) , Fürther Straße 250, 90429 Nürnberg, Germany
| | | | | | | | - Maksym V Kovalenko
- Department of Chemistry and Applied Biosciences, ETH Zürich , Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland
- Empa - Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Wolfgang Heiss
- Materials for Electronics and Energy Technology (i-MEET), Friedrich-Alexander-Universität Erlangen-Nürnberg , Martensstraße 7, 91058 Erlangen, Germany
- Energie Campus Nürnberg (EnCN) , Fürther Straße 250, 90429 Nürnberg, Germany
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180
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Binetti E, Striccoli M, Sibillano T, Giannini C, Brescia R, Falqui A, Comparelli R, Corricelli M, Tommasi R, Agostiano A, Curri ML. Tuning light emission of PbS nanocrystals from infrared to visible range by cation exchange. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2015; 16:055007. [PMID: 27877842 PMCID: PMC5070028 DOI: 10.1088/1468-6996/16/5/055007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/06/2015] [Accepted: 10/08/2015] [Indexed: 06/06/2023]
Abstract
Colloidal semiconductor nanocrystals, with intense and sharp-line emission between red and near-infrared spectral regions, are of great interest for optoelectronic and bio-imaging applications. The growth of an inorganic passivation layer on nanocrystal surfaces is a common strategy to improve their chemical and optical stability and their photoluminescence quantum yield. In particular, cation exchange is a suitable approach for shell growth at the expense of the nanocrystal core size. Here, the cation exchange process is used to promote the formation of a CdS passivation layer on the surface of very small PbS nanocrystals (2.3 nm in diameter), blue shifting their optical spectra and yielding luminescent and stable nanostructures emitting in the range of 700-850 nm. Structural, morphological and compositional investigation confirms the nanocrystal size contraction after the cation-exchange process, while the PbS rock-salt crystalline phase is retained. Absorption and photoluminescence spectroscopy demonstrate the growth of a passivation layer with a decrease of the PbS core size, as inferred by the blue-shift of the excitonic peaks. The surface passivation strongly increases the photoluminescence intensity and the excited state lifetime. In addition, the nanocrystals reveal increased stability against oxidation over time. Thanks to their absorption and emission spectral range and the slow recombination dynamics, such highly luminescent nano-objects can find interesting applications in sensitized photovoltaic cells and light-emitting devices.
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Affiliation(s)
- Enrico Binetti
- CNR-IPCF Div. Bari, c/o Department of Chemistry, via Orabona 4, 70126 Bari, Italy
| | - Marinella Striccoli
- CNR-IPCF Div. Bari, c/o Department of Chemistry, via Orabona 4, 70126 Bari, Italy
| | - Teresa Sibillano
- CNR- IC Institute of Crystallography, National Research Council, Via Amendola 122/O, 70126 Bari, Italy
| | - Cinzia Giannini
- CNR- IC Institute of Crystallography, National Research Council, Via Amendola 122/O, 70126 Bari, Italy
| | - Rosaria Brescia
- Nanochemistry Department, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova, Italy
| | - Andrea Falqui
- Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), 23955-6900 Thuwal, Kingdom of Saudi Arabia
| | - Roberto Comparelli
- CNR-IPCF Div. Bari, c/o Department of Chemistry, via Orabona 4, 70126 Bari, Italy
| | - Michela Corricelli
- CNR-IPCF Div. Bari, c/o Department of Chemistry, via Orabona 4, 70126 Bari, Italy
- Department of Chemistry, University of Bari Aldo Moro, Via Orabona 4, 70126 Bari, Italy
| | - Raffaele Tommasi
- CNR-IPCF Div. Bari, c/o Department of Chemistry, via Orabona 4, 70126 Bari, Italy
- Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari Aldo Moro, Piazza G. Cesare 11, 70124 Bari, Italy
| | - Angela Agostiano
- CNR-IPCF Div. Bari, c/o Department of Chemistry, via Orabona 4, 70126 Bari, Italy
- Department of Chemistry, University of Bari Aldo Moro, Via Orabona 4, 70126 Bari, Italy
| | - M Lucia Curri
- CNR-IPCF Div. Bari, c/o Department of Chemistry, via Orabona 4, 70126 Bari, Italy
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181
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Hrubaru M, Onwudiwe DC, Hosten E. Synthesis and properties of ZnS nanoparticles by solvothermal and pyrolysis routes using the Zn dithiocarbamate complex as novel single source precursor. J Sulphur Chem 2015. [DOI: 10.1080/17415993.2015.1080707] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Madalina Hrubaru
- C.D Nenitescu Center of organic chemistry of the Romania Academy, Splaiul Independentei, 2023, Bucharest, Romania
| | - Damian C. Onwudiwe
- Faculty of Agriculture, Science and Technology, Material Science Innovation and Modelling (MaSIM) Research Focus Area, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho, South Africa
- Department of Chemistry, School of Mathematical and Physical Sciences Faculty of Agriculture, Science and Technology, North-West University (Mafikeng Campus), Private Bag X2046, Mmabatho 2735, South Africa
| | - Eric Hosten
- Department of Chemistry, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa
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182
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Devadoss A, Sudhagar P, Terashima C, Nakata K, Fujishima A. Photoelectrochemical biosensors: New insights into promising photoelectrodes and signal amplification strategies. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2015. [DOI: 10.1016/j.jphotochemrev.2015.06.002] [Citation(s) in RCA: 140] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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183
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Investigation on ligand exchange kinetics at CdSe/ZnS quantum dot surface utilizing pyrene as flourescent probe. Chem Res Chin Univ 2015. [DOI: 10.1007/s40242-015-5110-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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184
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Soriano RB, Wu J, Kanatzidis MG. Size as a Parameter to Stabilize New Phases: Rock Salt Phases of PbmSb2nSem+3n. J Am Chem Soc 2015; 137:9937-42. [DOI: 10.1021/jacs.5b05562] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Ronald B. Soriano
- Department of Chemistry and ‡Department of Material Science, Northwestern University, Evanston, Illinois 60208 United States
| | - Jinsong Wu
- Department of Chemistry and ‡Department of Material Science, Northwestern University, Evanston, Illinois 60208 United States
| | - Mercouri G. Kanatzidis
- Department of Chemistry and ‡Department of Material Science, Northwestern University, Evanston, Illinois 60208 United States
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185
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Vörös M, Galli G, Zimanyi GT. Colloidal Nanoparticles for Intermediate Band Solar Cells. ACS NANO 2015; 9:6882-6890. [PMID: 26042468 DOI: 10.1021/acsnano.5b00332] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The Intermediate Band (IB) solar cell concept is a promising idea to transcend the Shockley-Queisser limit. Using the results of first-principles calculations, we propose that colloidal nanoparticles (CNPs) are a viable and efficient platform for the implementation of the IB solar cell concept. We focused on CdSe CNPs and we showed that intragap states present in the isolated CNPs with reconstructed surfaces combine to form an IB in arrays of CNPs, which is well separated from the valence and conduction band edges. We demonstrated that optical transitions to and from the IB are active. We also showed that the IB can be electron doped in a solution, e.g., by decamethylcobaltocene, thus activating an IB-induced absorption process. Our results, together with the recent report of a nearly 10% efficient CNP solar cell, indicate that colloidal nanoparticle intermediate band solar cells are a promising platform to overcome the Shockley-Queisser limit.
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Affiliation(s)
- Márton Vörös
- †Department of Physics, University of California, Davis, California 95616, United States
- ‡Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Giulia Galli
- ‡Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
- #Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Gergely T Zimanyi
- †Department of Physics, University of California, Davis, California 95616, United States
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186
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Zaiats G, Shapiro A, Yanover D, Kauffmann Y, Sashchiuk A, Lifshitz E. Optical and Electronic Properties of Nonconcentric PbSe/CdSe Colloidal Quantum Dots. J Phys Chem Lett 2015; 6:2444-2448. [PMID: 26266716 DOI: 10.1021/acs.jpclett.5b00498] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Lead chalcogenide colloidal quantum dots are attractive candidates for applications operating in the near infrared spectral range. However, their function is forestalled by limited stability under ambient conditions. Prolonged temperature-activated cation-exchange of Cd(2+) for Pb(2+) forms PbSe/CdSe core/shell heterostructures, unveiling a promising surface passivation route and a method to modify the dots' electronic properties. Here, we follow early stages of an-exchange process, using spectroscopic and structural characterization tools, as well as numerical calculations. We illustrate that preliminary-exchange stages involve the formation of nonconcentric heterostructures, presumably due to a facet selective reaction, showing a pronounced change in the optical properties upon the increase of the degree of nonconcentricity or/and plausible creation of core/shell interfacial alloying. However, progressive-exchange stages lead to rearrangement of the shell segment into uniform coverage, providing tolerance to oxygen exposure with a spectral steadiness already on the formation of a monolayer shell.
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Affiliation(s)
- Gary Zaiats
- §Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200025, Israel
| | - Arthur Shapiro
- §Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200025, Israel
| | - Diana Yanover
- §Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200025, Israel
| | - Yaron Kauffmann
- †Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 3200025, Israel
| | - Aldona Sashchiuk
- §Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200025, Israel
| | - Efrat Lifshitz
- §Schulich Faculty of Chemistry, Solid State Institute, Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200025, Israel
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187
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188
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Gui R, Jin H, Wang Z, Tan L. Recent advances in synthetic methods and applications of colloidal silver chalcogenide quantum dots. Coord Chem Rev 2015. [DOI: 10.1016/j.ccr.2015.03.023] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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189
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Gong K, Kelley DF. A predictive model of shell morphology in CdSe/CdS core/shell quantum dots. J Chem Phys 2015; 141:194704. [PMID: 25416902 DOI: 10.1063/1.4901428] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Lattice mismatch in core/shell nanoparticles occurs when the core and shell materials have different lattice parameters. When there is a significant lattice mismatch, a coherent core-shell interface results in substantial lattice strain energy, which can affect the shell morphology. The shell can be of uniform thickness or can be rough, having thin and thick regions. A smooth shell minimizes the surface energy at the expense of increased lattice strain energy and a rough shell does the opposite. A quantitative treatment of the lattice strain energy in determining the shell morphology of CdSe/CdS core/shell nanoparticles is presented here. We use the inhomogeneity in hole tunneling rates through the shell to adsorbed hole acceptors to quantify the extent of shell thickness inhomogeneity. The results can be understood in terms of a model based on elastic continuum calculations, which indicate that the lattice strain energy depends on both core size and shell thickness. The model assumes thermodynamic equilibrium, i.e., that the shell morphology corresponds to a minimum total (lattice strain plus surface) energy. Comparison with the experimental results indicates that CdSe/CdS nanoparticles undergo an abrupt transition from smooth to rough shells when the total lattice strain energy exceeds about 27 eV or the strain energy density exceeds 0.59 eV/nm(2). We also find that the predictions of this model are not followed for CdSe/CdS nanoparticles when the shell is deposited at very low temperature and therefore equilibrium is not established.
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Affiliation(s)
- Ke Gong
- Chemistry and Chemical Biology, University of California, Merced, 5200 North Lake Road, Merced, California 95343, USA
| | - David F Kelley
- Chemistry and Chemical Biology, University of California, Merced, 5200 North Lake Road, Merced, California 95343, USA
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190
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Chou KF, Dennis AM. Förster Resonance Energy Transfer between Quantum Dot Donors and Quantum Dot Acceptors. SENSORS 2015; 15:13288-325. [PMID: 26057041 PMCID: PMC4507609 DOI: 10.3390/s150613288] [Citation(s) in RCA: 182] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 05/29/2015] [Accepted: 06/01/2015] [Indexed: 01/27/2023]
Abstract
Förster (or fluorescence) resonance energy transfer amongst semiconductor quantum dots (QDs) is reviewed, with particular interest in biosensing applications. The unique optical properties of QDs provide certain advantages and also specific challenges with regards to sensor design, compared to other FRET systems. The brightness and photostability of QDs make them attractive for highly sensitive sensing and long-term, repetitive imaging applications, respectively, but the overlapping donor and acceptor excitation signals that arise when QDs serve as both the donor and acceptor lead to high background signals from direct excitation of the acceptor. The fundamentals of FRET within a nominally homogeneous QD population as well as energy transfer between two distinct colors of QDs are discussed. Examples of successful sensors are highlighted, as is cascading FRET, which can be used for solar harvesting.
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Affiliation(s)
- Kenny F Chou
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
| | - Allison M Dennis
- Department of Biomedical Engineering and Division of Materials Science and Engineering, Boston University, Boston, MA 02215, USA.
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191
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Synthesis and characterization of composition-gradient based CdxZn1−xSeyS1−y heterostructured quantum dots. REACTION KINETICS MECHANISMS AND CATALYSIS 2015. [DOI: 10.1007/s11144-014-0813-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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192
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Zhang Y, Newton B, Lewis E, Fu PP, Kafoury R, Ray PC, Yu H. Cytotoxicity of organic surface coating agents used for nanoparticles synthesis and stability. Toxicol In Vitro 2015; 29:762-8. [PMID: 25746383 PMCID: PMC4396871 DOI: 10.1016/j.tiv.2015.01.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 12/31/2014] [Accepted: 01/02/2015] [Indexed: 10/23/2022]
Abstract
Impact on health by nanomaterials has become a public concern with the great advances of nanomaterials for various applications. Surface coating agents are an integral part of nanoparticles, but not enough attention has been paid during toxicity tests of nanoparticles. As a result, there are inconsistent toxicity results for certain nanomaterials. In this study, we explored the cytotoxicity of eleven commonly used surface coating agents in two cell lines, human epidermal keratinocyte (HaCaT) and lung fibroblast (CRL-1490) cells, at surface coating agent concentrations of 3, 10, 30, and 100 μM. Two exposure time points, 2 h and 24 h, were employed for the study. Six of the eleven surface coating agents are cytotoxic, especially those surfactants with long aliphatic chains, both cationic (cetyltrimethylammonium bromide, oleylamine, tetraoctylammonium bromide, and hexadecylamine) and anionic (sodium dodecylsulfate). In addition, exposure time and the use of different cell lines also affect the cytotoxicity results. Therefore, factors such as cell lines used and exposure times must be considered when conducting toxicity tests or comparing cytotoxicity results.
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Affiliation(s)
- Ying Zhang
- Departments of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39127, USA
| | - Brandon Newton
- Departments of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39127, USA
| | - Eybriunna Lewis
- Departments of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39127, USA
| | - Peter P Fu
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
| | - Ramzi Kafoury
- Departments of Biology, Jackson State University, Jackson, MS 39127, USA
| | - Paresh C Ray
- Departments of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39127, USA
| | - Hongtao Yu
- Departments of Chemistry and Biochemistry, Jackson State University, Jackson, MS 39127, USA.
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193
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Kilina S, Kilin D, Tretiak S. Light-Driven and Phonon-Assisted Dynamics in Organic and Semiconductor Nanostructures. Chem Rev 2015; 115:5929-78. [DOI: 10.1021/acs.chemrev.5b00012] [Citation(s) in RCA: 140] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Svetlana Kilina
- Chemistry
and Biochemistry Department, North Dakota State University, Fargo, North Dakota 5810, United States
| | - Dmitri Kilin
- Department
of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
| | - Sergei Tretiak
- Theoretical
Division, Center for Nonlinear Studies (CNLS) and Center for Integrated
Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
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194
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Preparation of compact biocompatible quantum dots using multicoordinating molecular-scale ligands based on a zwitterionic hydrophilic motif and lipoic acid anchors. Nat Protoc 2015; 10:859-74. [DOI: 10.1038/nprot.2015.050] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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195
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Hu H, Wang K, Long H, Liu W, Wang B, Lu P. Precise Determination of the Crystallographic Orientations in Single ZnS Nanowires by Second-Harmonic Generation Microscopy. NANO LETTERS 2015; 15:3351-3357. [PMID: 25867087 DOI: 10.1021/acs.nanolett.5b00607] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report on the systematical study of the second-harmonic generation (SHG) in single zinc sulfide nanowires (ZnS NWs). The high-quality ZnS NWs with round cross-section were fabricated by chemical vapor deposition method. The transmission electron microscopy images show that the actual growth axis has a deviation angle of 0°∼20° with the preferential growth direction [120], which leads to the various polarization-dependent SHG response patterns in different individual ZnS NWs. The SHG response is quite sensitive to the orientations of c axis as well as the (100) and (010) crystal-axis of ZnS NWs; thus, all the three crystal-axis orientations of ZnS NWs are precisely determined by the SHG method. A high SHG conversion efficiency of 7 × 10(-6) is obtained in single ZnS NWs, which shows potential applications in nanoscale ultraviolet light source, nonlinear optical microscopy, and nanophotonic devices.
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Affiliation(s)
- Hongbo Hu
- †Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Kai Wang
- †Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Hua Long
- †Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Weiwei Liu
- †Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Bing Wang
- †Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Peixiang Lu
- †Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
- ‡Laboratory for Optical Information Technology, Wuhan Institute of Technology, Wuhan 430205, China
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196
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Liu J, Zhao Q, Liu JL, Wu YS, Cheng Y, Ji MW, Qian HM, Hao WC, Zhang LJ, Wei XJ, Wang SG, Zhang JT, Du Y, Dou SX, Zhu HS. Heterovalent-Doping-Enabled Efficient Dopant Luminescence and Controllable Electronic Impurity Via a New Strategy of Preparing II-VI Nanocrystals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2015; 27:2753-2761. [PMID: 25821075 DOI: 10.1002/adma.201500247] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 02/12/2015] [Indexed: 06/04/2023]
Abstract
Substitutional heterovalent doping represents an effective method to control the optical and electronic properties of nanocrystals (NCs). Highly monodisperse II-VI NCs with deep substitutional dopants are presented. The NCs exhibit stable, dominant, and strong dopant fluorescence, and control over n- and p-type electronic impurities is achieved. Large-scale, bottom-up superlattices of the NCs will speed up their application in electronic devices.
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Affiliation(s)
- Jian Liu
- Research Center of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, P.R. China
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197
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Mazibuko Z, Choonara YE, Kumar P, Du Toit LC, Modi G, Naidoo D, Pillay V. A Review of the Potential Role of Nano-Enabled Drug Delivery Technologies in Amyotrophic Lateral Sclerosis: Lessons Learned from Other Neurodegenerative Disorders. J Pharm Sci 2015; 104:1213-29. [DOI: 10.1002/jps.24322] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 11/27/2014] [Accepted: 12/04/2014] [Indexed: 12/11/2022]
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198
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Ferrari AC, Bonaccorso F, Fal'ko V, Novoselov KS, Roche S, Bøggild P, Borini S, Koppens FHL, Palermo V, Pugno N, Garrido JA, Sordan R, Bianco A, Ballerini L, Prato M, Lidorikis E, Kivioja J, Marinelli C, Ryhänen T, Morpurgo A, Coleman JN, Nicolosi V, Colombo L, Fert A, Garcia-Hernandez M, Bachtold A, Schneider GF, Guinea F, Dekker C, Barbone M, Sun Z, Galiotis C, Grigorenko AN, Konstantatos G, Kis A, Katsnelson M, Vandersypen L, Loiseau A, Morandi V, Neumaier D, Treossi E, Pellegrini V, Polini M, Tredicucci A, Williams GM, Hong BH, Ahn JH, Kim JM, Zirath H, van Wees BJ, van der Zant H, Occhipinti L, Di Matteo A, Kinloch IA, Seyller T, Quesnel E, Feng X, Teo K, Rupesinghe N, Hakonen P, Neil SRT, Tannock Q, Löfwander T, Kinaret J. Science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems. NANOSCALE 2015; 7:4598-810. [PMID: 25707682 DOI: 10.1039/c4nr01600a] [Citation(s) in RCA: 985] [Impact Index Per Article: 109.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We present the science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems, targeting an evolution in technology, that might lead to impacts and benefits reaching into most areas of society. This roadmap was developed within the framework of the European Graphene Flagship and outlines the main targets and research areas as best understood at the start of this ambitious project. We provide an overview of the key aspects of graphene and related materials (GRMs), ranging from fundamental research challenges to a variety of applications in a large number of sectors, highlighting the steps necessary to take GRMs from a state of raw potential to a point where they might revolutionize multiple industries. We also define an extensive list of acronyms in an effort to standardize the nomenclature in this emerging field.
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Affiliation(s)
- Andrea C Ferrari
- Cambridge Graphene Centre, University of Cambridge, Cambridge, CB3 0FA, UK.
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199
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Yi C, Knappenberger KL. The influence of surface passivation on electronic energy relaxation dynamics of CdSe and CdSe/CdS nanocrystals studied using visible and near infrared transient absorption spectroscopy. NANOSCALE 2015; 7:5884-5891. [PMID: 25761249 DOI: 10.1039/c4nr07581a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Charge carrier relaxation dynamics of electronically excited CdSe and CdSe/CdS core/shell nanocrystals (NCs) were studied using femtosecond time-resolved transient absorption spectroscopy, employing both visible and near-infrared (NIR) probe laser pulses. Following 400 nm excitation, the combination of visible and NIR laser probe pulses were used to determine the influence of surface passivation on electronic relaxation dynamics for nanocrystals overcoated with either organic ligands or inorganic semiconductors. In particular, low-energy NIR photons were used to isolate transient absorption signals due to either electron and hole intraband transitions. Four relaxation components were detected for CdSe NCs passivated by organic molecules: (1) picosecond hole relaxation; (2) electron deep trapping; (3) electron surface trapping; and (4) exciton radiative recombination. Based on TA data collected over a broad energy range, electron deep trapping at Se(2-) sites was suppressed for CdSe NCs passivated by inorganic (CdS) semiconducting materials. By comparing the time-dependent transient absorption data of a series of CdSe/CdS NCs with different shell thicknesses, evidence for the transition from Type-I to quasi Type-II NCs was obtained. These data illustrate the sensitivity of femtosecond time-resolved transient absorption measurements carried out over visible and near infrared probe energies for determining the influence of nanocrystal structure on electronic relaxation dynamics.
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Affiliation(s)
- Chongyue Yi
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA.
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200
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Yamashita SI, Hamada M, Nakanishi S, Saito H, Nosaka Y, Wakida SI, Biju V. Auger Ionization Beats Photo-Oxidation of Semiconductor Quantum Dots: Extended Stability of Single-Molecule Photoluminescence. Angew Chem Int Ed Engl 2015; 54:3892-6. [DOI: 10.1002/anie.201501131] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Indexed: 12/31/2022]
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