1
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Cheong IT, Yang Szepesvari L, Ni C, Butler C, O'Connor KM, Hooper R, Meldrum A, Veinot JGC. Not all silicon quantum dots are equal: photostability of silicon quantum dots with and without a thick amorphous shell. NANOSCALE 2024; 16:592-603. [PMID: 38058198 DOI: 10.1039/d3nr04478e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Luminescent colloidal silicon quantum dots (SiQDs) are sustainable alternatives to metal-based QDs for various optical applications. While the materials are reliant on their photoluminescence efficiency, the relationship between the structure and photostability of SiQDs is yet to be well studied. An amorphous silicon (a-Si) shell was recently discovered in SiQDs prepared by thermally-processed silicon oxides. As a-Si is known as a source of defects upon UV irradiation, the disordered shell could potentially have an adverse effect on the optical properties of nanoparticles. Herein, the photostability of ∼5 nm diameter SiQDs with an amorphous shell was compared with that of over-etched SiQDs of equivalent dimensions that bore an a-Si shell of negligible thickness. An UV-induced degradation study was conducted by subjecting toluene solutions of SiQDs to 365 nm light-emitting diodes (LEDs) under an inert atmosphere for predetermined times up to 72 hours. The structure, composition, and optical responses of the exposed SiQDs were evaluated.
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Affiliation(s)
- I Teng Cheong
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | | | - Chuyi Ni
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | - Cole Butler
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | - Kevin M O'Connor
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | - Riley Hooper
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | - Alkiviathes Meldrum
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Jonathan G C Veinot
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
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2
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Han Y, Iduoku K, Grant G, Rasulev B, Leontyev A, Hobbie EK, Tretiak S, Kilina SV, Kilin DS. Hot Carrier Dynamics at Ligated Silicon(111) Surfaces: A Computational Study. J Phys Chem Lett 2021; 12:7504-7511. [PMID: 34342460 DOI: 10.1021/acs.jpclett.1c02084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We provide a case-study for thermal grafting of benzenediazonium bromide onto a hydrogenated Si(111) surface using ab initio molecular dynamics (AIMD) calculations. A sequence of reaction steps is identified in the AIMD trajectory, including the loss of N2 from the diazonium salt, proton transfer from the surface to the bromide ion that eliminates HBr, and deposition of the phenyl group onto the surface. We next assess the influence of the phenyl groups on photophysics of hydrogen-terminated Si(111) slabs. The nonadiabatic couplings necessary for a description of the excited-state dynamics are calculated by combining ab initio electronic structures and reduced density matrix formalism with Redfield theory. The phenyl-terminated slab shows reduced nonradiative relaxation and recombination rates of hot charge carriers in comparison with the hydrogen-terminated slab. Altogether, our results provide atomistic insights revealing that (i) the diazonium salt thermally decomposes at the surface allowing the formation of covalently bonded phenyl group, and (ii) the coverage of phenyl groups on the surface slows down charge carrier cooling driven by electron-phonon interactions, which increases photoluminescence efficiency at the near-infrared spectral region.
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Affiliation(s)
- Yulun Han
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Kweeni Iduoku
- Department of Coatings and Polymeric Materials, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Gena Grant
- Turtle Mountain Community College, 10145 BIA Road 7, PO Box 340, Belcourt, North Dakota 58316, United States
| | - Bakhtiyor Rasulev
- Department of Coatings and Polymeric Materials, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Alexey Leontyev
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Erik K Hobbie
- Department of Physics, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Sergei Tretiak
- Theoretical Division and Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Svetlana V Kilina
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Dmitri S Kilin
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
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3
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Peng Y, Liu Q, Chen S. Structural Engineering of Semiconductor Nanoparticles by Conjugated Interfacial Bonds. CHEM REC 2020; 20:41-50. [DOI: 10.1002/tcr.201900010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 04/17/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Yi Peng
- Department of Chemistry and Biochemistry University of California 1156 High Street Santa Cruz CA 95064 USA
| | - Qiming Liu
- Department of Chemistry and Biochemistry University of California 1156 High Street Santa Cruz CA 95064 USA
| | - Shaowei Chen
- Department of Chemistry and Biochemistry University of California 1156 High Street Santa Cruz CA 95064 USA
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4
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Xin Y, Xu Y, Lee J, Shirai T. A novel and facile synthesis of visible photoluminescence Si nanocrystals by room temperature mechanochemical disproportionation of SiO. RSC Adv 2019; 9:8310-8314. [PMID: 35518703 PMCID: PMC9061880 DOI: 10.1039/c9ra00195f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 02/26/2019] [Indexed: 11/25/2022] Open
Abstract
Visible photoluminescence Si nanocrystals (Si NCs) are synthesized via a novel and facile room temperature mechanochemical disproportionation of SiO.![]()
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Affiliation(s)
- Yunzi Xin
- Advanced Ceramics Research Center, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi 466-8555 Japan
| | - Yuping Xu
- Advanced Ceramics Research Center, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi 466-8555 Japan
| | - Jeongbin Lee
- Advanced Ceramics Research Center, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi 466-8555 Japan
| | - Takashi Shirai
- Advanced Ceramics Research Center, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi 466-8555 Japan
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5
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Abdelhameed M, Aly S, Lant JT, Zhang X, Charpentier P. Energy/Electron Transfer Switch for Controlling Optical Properties of Silicon Quantum Dots. Sci Rep 2018; 8:17068. [PMID: 30459354 PMCID: PMC6244374 DOI: 10.1038/s41598-018-35201-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 11/01/2018] [Indexed: 12/18/2022] Open
Abstract
The superior optical properties of Silicon Quantum Dots (SQDs) have made them of increasing interest for a variety of biological and opto-electronic applications. The surface functionalization of the SQDs with aromatic ligands plays a key role in controlling their optical properties due to the interaction of the ligands with the electronic wave function of SQDs. However, there is limited reports in literature describing the impact of spacer groups connecting the aromatic chromophore to SQDs on the optical properties of the SQDs. Herein, we report the synthesis of two SQDs assemblies (1.6 nm average diameter) functionalized with perylene-3,4,9,10-tetracarboxylic acid diimide (PDI) chromophore through N-propylurea and propylamine spacers. Depending on the nature of the spacer, the photophysical measurements provide clear evidence for efficient energy and/or electron transfer between the SQDs and PDI. Energy transfer was confirmed to be the operative process when propylurea spacer was used, in which the rate was estimated to be ~2 × 109 s-1. On the other hand, the propylamine spacer was found to facilitate electron transfer process within the SQDs assembly. To illustrate functionality, the water soluble SQD-N-propylurea-PDI assembly was proven to be nontoxic and efficient for fluorescent imaging of embryonic kidney HEK293 cells and human bone cancerous U2OS cells.
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Affiliation(s)
- Mohammed Abdelhameed
- Department of Chemical and Biochemical Engineering, Western University, London, Ontario, N6A 5B9, Canada
| | - Shawkat Aly
- Department of Mechanical and Materials Engineering, Western University, London, Ontario, N6A 5B9, Canada
| | - Jeremy T Lant
- Department of Biochemistry, Western University, London, Ontario, N6A 5B9, Canada
| | - Xiaoran Zhang
- Department of Chemical and Biochemical Engineering, Western University, London, Ontario, N6A 5B9, Canada
| | - Paul Charpentier
- Department of Chemical and Biochemical Engineering, Western University, London, Ontario, N6A 5B9, Canada.
- Department of Mechanical and Materials Engineering, Western University, London, Ontario, N6A 5B9, Canada.
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6
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Kocevski V. Temperature dependence of radiative lifetimes, optical and electronic properties of silicon nanocrystals capped with various organic ligands. J Chem Phys 2018; 149:054301. [DOI: 10.1063/1.5039281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- V. Kocevski
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, S-751 20 Uppsala, Sweden
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7
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Carroll GM, Limpens R, Neale NR. Tuning Confinement in Colloidal Silicon Nanocrystals with Saturated Surface Ligands. NANO LETTERS 2018; 18:3118-3124. [PMID: 29659285 DOI: 10.1021/acs.nanolett.8b00680] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The optical properties of silicon nanocrystals (Si NCs) are a subject of intense study and continued debate. In particular, Si NC photoluminescence (PL) properties are known to depend strongly on the surface chemistry, resulting in electron-hole recombination pathways derived from the Si NC band-edge, surface-state defects, or combined NC-conjugated ligand hybrid states. In this Letter, we perform a comparison of three different saturated surface functional groups-alkyls, amides, and alkoxides-on nonthermal plasma-synthesized Si NCs. We find a systematic and size-dependent high-energy (blue) shift in the PL spectrum of Si NCs with amide and alkoxy functionalization relative to alkyl. Time-resolved photoluminescence and transient absorption spectroscopies reveal no change in the excited-state dynamics between Si NCs functionalized with alkyl, amide, or alkoxide ligands, showing for the first time that saturated ligands-not only surface-derived charge-transfer states or hybridization between NC and low-lying ligand orbitals-are responsible for tuning the Si NC optical properties. To explain these PL shifts we propose that the atom bound to the Si NC surface strongly interacts with the Si NC electronic wave function and modulates the Si NC quantum confinement. These results reveal a potentially broadly applicable correlation between the optoelectronic properties of Si NCs and related quantum-confined structures based on the interaction between NC surfaces and the ligand binding group.
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Affiliation(s)
- Gerard M Carroll
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
| | - Rens Limpens
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
| | - Nathan R Neale
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
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8
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Liu XY, Xie XY, Fang WH, Cui G. Photoinduced relaxation dynamics of nitrogen-capped silicon nanoclusters: a TD-DFT study. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1433335] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Xiang-Yang Liu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Xiao-Ying Xie
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Wei-Hai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, China
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9
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Sacarescu L, Simionescu M, Sacarescu G, Quade A, Kolb JF, Miron C. Nanostructuration of polysilane-SiQDs composite by pulsed electrical discharges in water. REACT FUNCT POLYM 2017. [DOI: 10.1016/j.reactfunctpolym.2017.09.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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10
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de Weerd C, Shin Y, Marino E, Kim J, Lee H, Saeed S, Gregorkiewicz T. Comparison of the Optical Properties of Graphene and Alkyl-terminated Si and Ge Quantum Dots. Sci Rep 2017; 7:14463. [PMID: 29089509 PMCID: PMC5663913 DOI: 10.1038/s41598-017-12872-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 09/14/2017] [Indexed: 11/30/2022] Open
Abstract
Semiconductor quantum dots are widely investigated due to their size dependent energy structure. In particular, colloidal quantum dots represent a promising nanomaterial for optoelectronic devices, such as photodetectors and solar cells, but also luminescent markers for biotechnology, among other applications. Ideal materials for these applications should feature efficient radiative recombination and absorption transitions, altogether with spectral tunability over a wide range. Group IV semiconductor quantum dots can fulfill these requirements and serve as an alternative to the commonly used direct bandgap materials containing toxic and/or rare elements. Here, we present optical properties of butyl-terminated Si and Ge quantum dots and compare them to those of graphene quantum dots, finding them remarkably similar. We investigate their time-resolved photoluminescence emission as well as the photoluminescence excitation and linear absorption spectra. We contemplate that their emission characteristics indicate a (semi-) resonant activation of the emitting channel; the photoluminescence excitation shows characteristics similar to those of a molecule. The optical density is consistent with band-to-band absorption processes originating from core-related states. Hence, these observations strongly indicate a different microscopic origin for absorption and radiative recombination in the three investigated quantum dot systems.
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Affiliation(s)
- Chris de Weerd
- Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands.
| | - Yonghun Shin
- Centre for Integrated Nanostructure Physics, Institute of Basic Science, Department of Chemistry, Sungkyunkwan University, 2066 Seoburo, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea
| | - Emanuele Marino
- Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Joosung Kim
- Centre for Integrated Nanostructure Physics, Institute of Basic Science, Department of Energy Science, Sungkyunkwan University, 2066 Seoburo, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea
| | - Hyoyoung Lee
- Centre for Integrated Nanostructure Physics, Institute of Basic Science, Department of Chemistry, Sungkyunkwan University, 2066 Seoburo, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea.,Centre for Integrated Nanostructure Physics, Institute of Basic Science, Department of Energy Science, Sungkyunkwan University, 2066 Seoburo, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea
| | - Saba Saeed
- Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands.,Department of Physics, The Women University, Kutchery Campus, L.M.Q. Road, Multan, Pakistan
| | - Tom Gregorkiewicz
- Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands.
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11
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Xin Y, Kitasako T, Maeda M, Saitow KI. Solvent dependence of laser-synthesized blue-emitting Si nanoparticles: Size, quantum yield, and aging performance. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.02.060] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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Mazzaro R, Romano F, Ceroni P. Long-lived luminescence of silicon nanocrystals: from principles to applications. Phys Chem Chem Phys 2017; 19:26507-26526. [DOI: 10.1039/c7cp05208a] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Understanding parameters affecting the luminescence of silicon nanocrystals will guide the design of improved systems for a plethora of applications.
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Affiliation(s)
- Raffaello Mazzaro
- Department of Chemistry “Giacomo Ciamician”
- University of Bologna, and Interuniversity Center for the Chemical Conversion of Solar Energy (SolarChem)
- 40126 Bologna
- Italy
| | - Francesco Romano
- Department of Chemistry “Giacomo Ciamician”
- University of Bologna, and Interuniversity Center for the Chemical Conversion of Solar Energy (SolarChem)
- 40126 Bologna
- Italy
| | - Paola Ceroni
- Department of Chemistry “Giacomo Ciamician”
- University of Bologna, and Interuniversity Center for the Chemical Conversion of Solar Energy (SolarChem)
- 40126 Bologna
- Italy
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13
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Kislitsyn DA, Mills JM, Kocevski V, Chiu SK, DeBenedetti WJI, Gervasi CF, Taber BN, Rosenfield AE, Eriksson O, Rusz J, Goforth AM, Nazin GV. Communication: Visualization and spectroscopy of defects induced by dehydrogenation in individual silicon nanocrystals. J Chem Phys 2016; 144:241102. [DOI: 10.1063/1.4954833] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Dmitry A. Kislitsyn
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Jon M. Mills
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Vancho Kocevski
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Sheng-Kuei Chiu
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
| | | | - Christian F. Gervasi
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Benjamen N. Taber
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Ariel E. Rosenfield
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
| | - Olle Eriksson
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Ján Rusz
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala, Sweden
| | - Andrea M. Goforth
- Department of Chemistry, Portland State University, Portland, Oregon 97201, USA
| | - George V. Nazin
- Department of Chemistry and Biochemistry, Materials Science Institute, Oregon Center for Optical, Molecular and Quantum Science, University of Oregon, 1253 University of Oregon, Eugene, Oregon 97403, USA
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14
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Nehaniv CL, Rhodes J, Egri-Nagy A, Dini P, Morris ER, Horváth G, Karimi F, Schreckling D, Schilstra MJ. Symmetry structure in discrete models of biochemical systems: natural subsystems and the weak control hierarchy in a new model of computation driven by interactions. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2015; 373:rsta.2014.0223. [PMID: 26078349 DOI: 10.1098/rsta.2014.0223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/27/2015] [Indexed: 06/04/2023]
Abstract
Interaction computing is inspired by the observation that cell metabolic/regulatory systems construct order dynamically, through constrained interactions between their components and based on a wide range of possible inputs and environmental conditions. The goals of this work are to (i) identify and understand mathematically the natural subsystems and hierarchical relations in natural systems enabling this and (ii) use the resulting insights to define a new model of computation based on interactions that is useful for both biology and computation. The dynamical characteristics of the cellular pathways studied in systems biology relate, mathematically, to the computational characteristics of automata derived from them, and their internal symmetry structures to computational power. Finite discrete automata models of biological systems such as the lac operon, the Krebs cycle and p53-mdm2 genetic regulation constructed from systems biology models have canonically associated algebraic structures (their transformation semigroups). These contain permutation groups (local substructures exhibiting symmetry) that correspond to 'pools of reversibility'. These natural subsystems are related to one another in a hierarchical manner by the notion of 'weak control'. We present natural subsystems arising from several biological examples and their weak control hierarchies in detail. Finite simple non-Abelian groups are found in biological examples and can be harnessed to realize finitary universal computation. This allows ensembles of cells to achieve any desired finitary computational transformation, depending on external inputs, via suitably constrained interactions. Based on this, interaction machines that grow and change their structure recursively are introduced and applied, providing a natural model of computation driven by interactions.
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Affiliation(s)
- Chrystopher L Nehaniv
- Royal Society Wolfson Biocomputation Research Laboratory, University of Hertfordshire, Hatfield AL10 9AB, UK
| | - John Rhodes
- Department of Mathematics, University of California Berkeley, Berkeley, CA 94720, USA
| | - Attila Egri-Nagy
- Royal Society Wolfson Biocomputation Research Laboratory, University of Hertfordshire, Hatfield AL10 9AB, UK Centre for Research in Mathematics, University of Western Sydney, Locked Bag 1797, Penrith, New South Wales 2751, Australia
| | - Paolo Dini
- Royal Society Wolfson Biocomputation Research Laboratory, University of Hertfordshire, Hatfield AL10 9AB, UK
| | - Eric Rothstein Morris
- Institute of IT Security and Security Law, University of Passau, Passau 94030, Germany
| | - Gábor Horváth
- Institute of Mathematics, University of Debrecen, Pf. 12. Debrecen, 4010 Hungary
| | - Fariba Karimi
- Royal Society Wolfson Biocomputation Research Laboratory, University of Hertfordshire, Hatfield AL10 9AB, UK
| | - Daniel Schreckling
- Institute of IT Security and Security Law, University of Passau, Passau 94030, Germany
| | - Maria J Schilstra
- Royal Society Wolfson Biocomputation Research Laboratory, University of Hertfordshire, Hatfield AL10 9AB, UK
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15
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Zhou T, Anderson RT, Li H, Bell J, Yang Y, Gorman BP, Pylypenko S, Lusk MT, Sellinger A. Bandgap Tuning of Silicon Quantum Dots by Surface Functionalization with Conjugated Organic Groups. NANO LETTERS 2015; 15:3657-3663. [PMID: 25971956 DOI: 10.1021/nl504051x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The quantum confinement and enhanced optical properties of silicon quantum dots (SiQDs) make them attractive as an inexpensive and nontoxic material for a variety of applications such as light emitting technologies (lighting, displays, sensors) and photovoltaics. However, experimental demonstration of these properties and practical application into optoelectronic devices have been limited as SiQDs are generally passivated with covalently bound insulating alkyl chains that limit charge transport. In this work, we show that strategically designed triphenylamine-based surface ligands covalently bonded to the SiQD surface using conjugated vinyl connectivity results in a 70 nm red-shifted photoluminescence relative to their decyl-capped control counterparts. This suggests that electron density from the SiQD is delocalized into the surface ligands to effectively create a larger hybrid QD with possible macroscopic charge transport properties.
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Affiliation(s)
- Tianlei Zhou
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Ryan T Anderson
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Huashan Li
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Jacob Bell
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Yongan Yang
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Brian P Gorman
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Svitlana Pylypenko
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Mark T Lusk
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Alan Sellinger
- †Department of Chemistry and Geochemistry, ‡Department of Physics, §Materials Science Program, ∥Metallurgical and Materials Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
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16
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Hwang J, Jeong Y, Lee KH, Seo Y, Kim J, Hong JW, Kamaloo E, Camesano TA, Choi J. Simple Preparation of Fluorescent Silicon Nanoparticles from Used Si Wafers. Ind Eng Chem Res 2015. [DOI: 10.1021/acs.iecr.5b00446] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jangsun Hwang
- Department
of Bionano Technology, Graduate School, Hanyang University, Seoul 133-791, Korea
| | - Yoon Jeong
- Department
of Bionano Technology, Graduate School, Hanyang University, Seoul 133-791, Korea
- Department
of Bionano Engineering, Hanyang University ERICA, Ansan, Gyeonggi 426-791, Korea
| | - Kwan Hong Lee
- Department
of Bionano Technology, Graduate School, Hanyang University, Seoul 133-791, Korea
- Department
of Bionano Engineering, Hanyang University ERICA, Ansan, Gyeonggi 426-791, Korea
- OpenView Venture
Partners, Boston, Massachusetts 02210, United States
| | - Youngmin Seo
- Department
of Bionano Technology, Graduate School, Hanyang University, Seoul 133-791, Korea
| | - Jieun Kim
- Department
of Bionano Technology, Graduate School, Hanyang University, Seoul 133-791, Korea
| | - Jong Wook Hong
- Department
of Bionano Technology, Graduate School, Hanyang University, Seoul 133-791, Korea
- Department
of Bionano Engineering, Hanyang University ERICA, Ansan, Gyeonggi 426-791, Korea
| | - Elaheh Kamaloo
- Department
of Chemical Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, United States
| | - Terri A. Camesano
- Department
of Chemical Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, United States
| | - Jonghoon Choi
- Department
of Bionano Technology, Graduate School, Hanyang University, Seoul 133-791, Korea
- Department
of Bionano Engineering, Hanyang University ERICA, Ansan, Gyeonggi 426-791, Korea
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17
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Wang H, Xu Z, Fink MJ, Shchukin D, Mitchell BS. Functionalized silicon nanoparticles from reactive cavitation erosion of silicon wafers. Chem Commun (Camb) 2015; 51:1465-8. [DOI: 10.1039/c4cc06991a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Sonochemical reactor used for reactive cavitation erosion formation of functionalized silicon nanoparticles.
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Affiliation(s)
- Hongqiang Wang
- Stephenson Institute for Renewable Energy
- Department of Chemistry
- University of Liverpool
- Peach Street
- Liverpool L69 7ZF
| | - Zejing Xu
- Department of Chemistry
- Tulane University
- New Orleans
- USA
| | - Mark J. Fink
- Department of Chemistry
- Tulane University
- New Orleans
- USA
| | - Dmitry Shchukin
- Stephenson Institute for Renewable Energy
- Department of Chemistry
- University of Liverpool
- Peach Street
- Liverpool L69 7ZF
| | - Brian S. Mitchell
- Department of Chemical and Biomolecular Engineering
- 300 Lindy Claiborne Boggs Center
- Tulane University
- New Orleans
- USA
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18
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Capan I, Carvalho A, Coutinho J. Silicon and germanium nanocrystals: properties and characterization. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2014; 5:1787-94. [PMID: 25383290 PMCID: PMC4222352 DOI: 10.3762/bjnano.5.189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 09/24/2014] [Indexed: 05/28/2023]
Abstract
Group-IV nanocrystals have emerged as a promising group of materials that extends the realm of application of bulk diamond, silicon, germanium and related materials beyond their traditional boundaries. Over the last two decades of research, their potential for application in areas such as optoelectronic applications and memory devices has been progressively unraveled. Nevertheless, new challenges with no parallel in the respective bulk material counterparts have arisen. In this review, we consider what has been achieved and what are the current limitations with regard to growth, characterization and modeling of silicon and germanium nanocrystals and related materials.
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Affiliation(s)
- Ivana Capan
- Rudjer Boskovic Institute, P.O. Box 180, 10000 Zagreb, Croatia
| | - Alexandra Carvalho
- Graphene Research Centre and Department of Physics, National University of Singapore, 117542, Singapore
| | - José Coutinho
- Department of Physics and I3N, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
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19
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Dohnalová K, Gregorkiewicz T, Kůsová K. Silicon quantum dots: surface matters. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:173201. [PMID: 24713583 DOI: 10.1088/0953-8984/26/17/173201] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Silicon quantum dots (SiQDs) hold great promise for many future technologies. Silicon is already at the core of photovoltaics and microelectronics, and SiQDs are capable of efficient light emission and amplification. This is crucial for the development of the next technological frontiers-silicon photonics and optoelectronics. Unlike any other quantum dots (QDs), SiQDs are made of non-toxic and abundant material, offering one of the spectrally broadest emission tunabilities accessible with semiconductor QDs and allowing for tailored radiative rates over many orders of magnitude. This extraordinary flexibility of optical properties is achieved via a combination of the spatial confinement of carriers and the strong influence of surface chemistry. The complex physics of this material, which is still being unraveled, leads to new effects, opening up new opportunities for applications. In this review we summarize the latest progress in this fascinating research field, with special attention given to surface-induced effects, such as the emergence of direct bandgap transitions, and collective effects in densely packed QDs, such as space separated quantum cutting.
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Affiliation(s)
- K Dohnalová
- Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, NL-1098 XH Amsterdam, The Netherlands
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20
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Li H, Wu Z, Zhou T, Sellinger A, Lusk MT. Tailoring the optical gap of silicon quantum dots without changing their size. Phys Chem Chem Phys 2014; 16:19275-81. [DOI: 10.1039/c4cp03042g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The optical gap of silicon quantum dots can be tailored, independent of their size, via direct generation of spatially separated excitons.
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Affiliation(s)
- Huashan Li
- Department of Physics
- Colorado School of Mines
- Golden, USA
| | - Zhigang Wu
- Department of Physics
- Colorado School of Mines
- Golden, USA
| | - Tianlei Zhou
- Department of Chemistry and Geochemistry
- Colorado School of Mines
- Golden, USA
| | - Alan Sellinger
- Department of Chemistry and Geochemistry
- Colorado School of Mines
- Golden, USA
| | - Mark T. Lusk
- Department of Physics
- Colorado School of Mines
- Golden, USA
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21
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Coxon PR, Ahire JH, Ashby SP, Frogley MD, Chao Y. Amine-terminated nanoparticle films: pattern deposition by a simple nanostencilling technique and stability studies under X-ray irradiation. Phys Chem Chem Phys 2014; 16:5817-23. [DOI: 10.1039/c3cp55344b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Exploring the surface chemistry of nanopatterned amine-terminated nanoparticle films.
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Affiliation(s)
- P. R. Coxon
- Energy Materials Laboratory
- School of Chemistry
- University of East Anglia
- Norwich, UK
- Department of Materials Science & Metallurgy
| | - J. H. Ahire
- Energy Materials Laboratory
- School of Chemistry
- University of East Anglia
- Norwich, UK
| | - S. P. Ashby
- Energy Materials Laboratory
- School of Chemistry
- University of East Anglia
- Norwich, UK
| | | | - Y. Chao
- Energy Materials Laboratory
- School of Chemistry
- University of East Anglia
- Norwich, UK
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22
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An ab initio study of the ground and excited states of mercaptoacetic acid-capped silicon quantum dots. MONATSHEFTE FUR CHEMIE 2013. [DOI: 10.1007/s00706-013-1020-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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23
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Abstract
Quantum confined silicon nanocrystals (Si-ncs) exhibit intriguing properties due to silicon's indirect bandgap and their highly reactive surfaces. In particular the interplay of quantum confinement with surface effects reveals a complex scenario, which can complicate the interpretation of Si-nc properties and prediction of their corresponding behaviour. At the same time, the complexity and interplay of the different mechanisms in Si-ncs offer great opportunities with characteristics that may not be achievable with other nano-systems. In this context, a variety of carefully surface-engineered Si-ncs are highly desirable both for improving our understanding of Si-nc photo-physics and for their successful integration in application devices. Here we firstly highlight a selection of theoretical efforts and experimental surface engineering approaches and secondly we focus on recent surface engineering results that have utilized novel plasma-liquid interactions.
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Affiliation(s)
- Davide Mariotti
- Nanotechnology & Integrated Bio-Engineering Centre-NIBEC, University of Ulster, UK.
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24
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Wang R, Pi X, Yang D. Surface modification of chlorine-passivated silicon nanocrystals. Phys Chem Chem Phys 2013; 15:1815-20. [DOI: 10.1039/c2cp43763e] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Dohnalová K, Fučíková A, Umesh CP, Humpolíčková J, Paulusse JMJ, Valenta J, Zuilhof H, Hof M, Gregorkiewicz T. Microscopic origin of the fast blue-green luminescence of chemically synthesized non-oxidized silicon quantum dots. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:3185-3191. [PMID: 22807258 DOI: 10.1002/smll.201200477] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 05/07/2012] [Indexed: 06/01/2023]
Abstract
The microscopic origin of the bright nanosecond blue-green photoluminescence (PL), frequently reported for synthesized organically terminated Si quantum dots (Si-QDs), has not been fully resolved, hampering potential applications of this interesting material. Here a comprehensive study of the PL from alkyl-terminated Si-QDs of 2-3 nm size, prepared by wet chemical synthesis is reported. Results obtained on the ensemble and those from the single nano-object level are compared, and they provide conclusive evidence that efficient and tunable emission arises due to radiative recombination of electron-hole pairs confined in the Si-QDs. This understanding paves the way towards applications of chemical synthesis for the development of Si-QDs with tunable sizes and bandgaps.
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Affiliation(s)
- Kateřina Dohnalová
- Van der Waals-Zeeman Institute, University of Amsterdam, Science Park 904, Amsterdam, NL-1098 XH, The Netherlands.
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26
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Hannah DC, Yang J, Podsiadlo P, Chan MKY, Demortière A, Gosztola DJ, Prakapenka VB, Schatz GC, Kortshagen U, Schaller RD. On the origin of photoluminescence in silicon nanocrystals: pressure-dependent structural and optical studies. NANO LETTERS 2012; 12:4200-4205. [PMID: 22757779 DOI: 10.1021/nl301787g] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A lack of consensus persists regarding the origin of photoluminescence in silicon nanocrystals. Here we report pressure-dependences of X-ray diffraction and photoluminescence from alkane-terminated colloidal particles. We determine the diamond-phase bulk modulus, observe multiple phase transitions, and importantly find a systematic photoluminescence red shift that matches the X(conduction)-to-Γ(valence) transition of bulk crystalline silicon. These results, reinforced by calculations, suggest that the efficient photoluminescence, frequently attributed to defects, arises instead from core-states that remain highly indirect despite quantum confinement.
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Affiliation(s)
- Daniel C Hannah
- Department of Chemistry, Northwestern University, Evanston Illinois 60208, USA
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27
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Liu P, Na N, Huang L, He D, Huang C, Ouyang J. The Application of Amine-Terminated Silicon Quantum Dots on the Imaging of Human Serum Proteins after Polyacrylamide Gel Electrophoresis (PAGE). Chemistry 2012; 18:1438-43. [DOI: 10.1002/chem.201102187] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Indexed: 11/05/2022]
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28
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Bywalez R, Karacuban H, Nienhaus H, Schulz C, Wiggers H. Stabilization of mid-sized silicon nanoparticles by functionalization with acrylic acid. NANOSCALE RESEARCH LETTERS 2012; 7:76. [PMID: 22248382 PMCID: PMC3312836 DOI: 10.1186/1556-276x-7-76] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 01/16/2012] [Indexed: 05/31/2023]
Abstract
We present an enhanced method to form stable dispersions of medium-sized silicon nanoparticles for solar cell applications by thermally induced grafting of acrylic acid to the nanoparticle surface. In order to confirm their covalent attachment on the silicon nanoparticles and to assess the quality of the functionalization, X-ray photoelectron spectroscopy and diffuse reflectance infrared Fourier spectroscopy measurements were carried out. The stability of the dispersion was elucidated by dynamic light scattering and Zeta-potential measurements, showing no sign of degradation for months.
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Affiliation(s)
- Robert Bywalez
- IVG, Institute for Combustion and Gasdynamics, University Duisburg-Essen, Duisburg, 47048, Germany
| | - Hatice Karacuban
- Faculty of Physics, University Duisburg-Essen, Duisburg, 47048, Germany
| | - Hermann Nienhaus
- Faculty of Physics, University Duisburg-Essen, Duisburg, 47048, Germany
- CeNIDE, Center for Nanointegration Duisburg-Essen, Duisburg, 47048, Germany
| | - Christof Schulz
- IVG, Institute for Combustion and Gasdynamics, University Duisburg-Essen, Duisburg, 47048, Germany
- CeNIDE, Center for Nanointegration Duisburg-Essen, Duisburg, 47048, Germany
| | - Hartmut Wiggers
- IVG, Institute for Combustion and Gasdynamics, University Duisburg-Essen, Duisburg, 47048, Germany
- CeNIDE, Center for Nanointegration Duisburg-Essen, Duisburg, 47048, Germany
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29
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Ni Z, Pi X, Yang D. Density functional theory study on a 1.4 nm silicon nanocrystal coated with carbon. RSC Adv 2012. [DOI: 10.1039/c2ra21537c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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30
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Harun NA, Horrocks BR, Fulton DA. A miniemulsion polymerization technique for encapsulation of silicon quantum dots in polymer nanoparticles. NANOSCALE 2011; 3:4733-4741. [PMID: 21984383 DOI: 10.1039/c1nr10938c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Miniemulsion polymerization techniques were used to encapsulate luminescent alkylated silicon quantum dots (Si-QDs) within polymer nanoparticles composed of styrene and 4-vinylbenzaldehyde monomers. The polymer nanoparticles had mean diameters in the range 90-150 nm depending on the reaction conditions, however all samples showed narrow particle size distributions, as determined by dynamic light scattering and atomic force microscopy. The Si-QDs were found to have a small, but beneficial effect on the polymerization process by reducing the polydispersity of the final polymer particles, which we attribute to co-surfactant action of the undecene used to form the alkyl capping layer on the Si-QDs. Confocal microspectroscopy was used to confirm that the luminescent alkylated Si-QDs were encapsulated within the polymer nanoparticles and also provided luminescence and Raman spectra which show peaks corresponding to both alkylated Si-QDs and the polymer nanoparticles. Treatment of the polymer nanoparticles with dilute aqueous sodium hydroxide solution, which is known to corrode Si and extinguish the luminescence of alkylated Si-QDs, results in only a partial reduction in luminescence suggesting that the majority of the alkylated Si-QDs are encapsulated sufficiently deep within the polymer matrix to protect them from alkaline attack. Miniemulsion polymerization of the monomers styrene and 4-vinylbenzaldehyde affords polymer nanoparticles displaying reactive aldehyde groups upon their surfaces, which could then be decorated with a selection of molecules through imine, oxime or hydrazone condensation reactions. We speculate that polymer-SiQD composite nanoparticles whose surfaces can be further decorated will increase the utility of luminescent Si-QDs in applications such as anti-counterfeiting and as probes of biological processes.
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Affiliation(s)
- Noor Aniza Harun
- Chemical Nanoscience Laboratory, School of Chemistry, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK
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31
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Ruizendaal L, Pujari SP, Gevaerts V, Paulusse JMJ, Zuilhof H. Biofunctional Silicon Nanoparticles by Means of Thiol-Ene Click Chemistry. Chem Asian J 2011; 6:2776-86. [DOI: 10.1002/asia.201100375] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Indexed: 12/29/2022]
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32
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Zdetsis AD. Functionalizable magnetic/luminous silicon/bismuth core/shell nanocrystalline particles. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.04.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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33
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Trani F, Barone V. Silicon Nanocrystal Functionalization: Analytic Fitting of DFTB Parameters. J Chem Theory Comput 2011; 7:713-9. [PMID: 26596303 DOI: 10.1021/ct1006086] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A density functional tight binding (DFTB) scheme has been applied to functionalized silicon nanocrystals. Using an analytic functional representation of DFTB parameters, the scheme has been used to compute the adsorption energies in the organic functionalization of reconstructed Si(100) and H-terminated Si(111) surfaces of hundreds-of-atoms nanocrystals. We adopt an ONIOM(QM:QM') approach that corrects the overbinding of DFTB, obtaining nice agreement with high-level reaction energies and structural configurations.
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Affiliation(s)
- Fabio Trani
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126, Pisa, Italy.,Infn Sezione di Pisa
| | - Vincenzo Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126, Pisa, Italy.,Infn Sezione di Pisa
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34
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Fan J, Chu PK. Group IV nanoparticles: synthesis, properties, and biological applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2010; 6:2080-98. [PMID: 20730824 DOI: 10.1002/smll.201000543] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In this review, the emerging roles of group IV nanoparticles including silicon, diamond, silicon carbide, and germanium are summarized and discussed from the perspective of biologists, engineers, and medical practitioners. The synthesis, properties, and biological applications of these new nanomaterials have attracted great interest in the past few years. They have gradually evolved into promising biomaterials due to their innate biocompatibility; toxic ions are not released when they are used in vitro or in vivo, and their wide fluorescence spectral regions span the near-infrared, visible, and near-ultraviolet ranges. Additionally, they generally have good resistance against photobleaching and have lifetimes on the order of nanoseconds to microseconds, which are suitable for bioimaging. Some of the materials possess unique mechanical, chemical, or physical properties, such as ultrachemical and thermal stability, high hardness, high photostability, and no blinking. Recent data have revealed the superiority of these nanoparticles in biological imaging and drug delivery.
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Affiliation(s)
- Jiyang Fan
- Department of Physics, Southeast University, Nanjing 211189, PR China.
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35
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Shirahata N, Tsuruoka T, Hasegawa T, Sakka Y. Size-tunable UV-luminescent silicon nanocrystals. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2010; 6:915-921. [PMID: 20397207 DOI: 10.1002/smll.200902236] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Affiliation(s)
- Naoto Shirahata
- National Institute for Materials Science (NIMS) 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
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36
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Shiohara A, Hanada S, Prabakar S, Fujioka K, Lim TH, Yamamoto K, Northcote PT, Tilley RD. Chemical reactions on surface molecules attached to silicon quantum dots. J Am Chem Soc 2010; 132:248-53. [PMID: 20000400 DOI: 10.1021/ja906501v] [Citation(s) in RCA: 158] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This Article describes research on chemical reactions on molecules attached to the surface of silicon quantum dots that have been performed to produce quantum dots with reactive surface functionalities such as diols and epoxides. Characterization of the surface reactions includes NMR and FT-IR studies, and the quantum dots were characterized by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). Cytotoxicity and cell viability assay conducted on silicon dots capped with polar molecules indicated low toxicity with quantum dots with more reactive functionalities found to be more toxic. The silicon quantum dots photoluminesce and have been used as a blue chromophore for the biological imaging of cells.
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Affiliation(s)
- Amane Shiohara
- School of Chemical and Physical Sciences, MacDiarmid Institute of Advanced Materials and Nanotechnology, Victoria University of Wellington, P.O. Box 600, Wellington, New Zealand
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37
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Heintz AS, Fink MJ, Mitchell BS. Silicon nanoparticles with chemically tailored surfaces. Appl Organomet Chem 2010. [DOI: 10.1002/aoc.1602] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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38
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Zhang DB, Dumitrică T. Modulating the optical and electronic properties of highly symmetric Si quantum dots. NANOTECHNOLOGY 2009; 20:445401. [PMID: 19809111 DOI: 10.1088/0957-4484/20/44/445401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The optical and electronic properties of quantum dots are critically influenced by the electronic states around the last occupied first empty levels. Using density functional theory calculations we show three alternative ways to alter the optical response of highly stable, highly symmetric hydrogen-terminated fullerene and polycrystalline Si quantum dots: small shape changes, applied uniaxial strain and exohedral doping. The demonstrated effectiveness renders symmetry lowering, the common theme of these processes, as a promising concept for deliberately adjusting optical response.
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Affiliation(s)
- D-B Zhang
- Department of Chemical Engineering and Materials Science, Institute of Technology, University of Minnesota, Minneapolis, MN 55455, USA
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39
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Gali A, Vörös M, Rocca D, Zimanyi GT, Galli G. High-energy excitations in silicon nanoparticles. NANO LETTERS 2009; 9:3780-3785. [PMID: 19785388 DOI: 10.1021/nl901970u] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We have investigated high energy excitations in approximately 1-2 nm Si nanoparticles (NPs) by ab initio time-dependent density functional calculations, focusing on the influence on excitation spectra, of surface reconstruction, surface passivation by alkyl groups, and the interaction between NPs. We have found that surface reconstruction may change excitation spectra dramatically at both low and high energies above the gap; absorption may be enhanced nonlinearly by the presence of alkyl groups, compared to that of unreconstructed, hydrogenated Si NPs, and by the interaction between NPs. Our findings can help interpret the recent experiments on multielectron generation in colloidal semiconductor NPs as well as help optimize photovoltaic applications of NPs.
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Affiliation(s)
- Adam Gali
- Department of Atomic Physics, Budapest University of Technology and Economics, Budafoki ut 8., H-1111, Budapest, Hungary.
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40
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Liptak RW, Devetter B, Thomas JH, Kortshagen U, Campbell SA. SF6 plasma etching of silicon nanocrystals. NANOTECHNOLOGY 2009; 20:035603. [PMID: 19417298 DOI: 10.1088/0957-4484/20/3/035603] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
An SF(6)-based plasma has been employed to perform in-flight etching of silicon nanocrystals (Si-NCs) after they were synthesized in an SiH(4)-based plasma. The photoluminescence of the Si-NCs blue-shifts after etching, indicating an etching-induced size reduction of the Si-NCs. It is shown that both the SF(6) plasma power and the flow rate can be utilized to control the etch rate (and thus the size reduction) of the Si-NCs. The SF(6) etched Si-NCs show only low concentrations of residual impurities other than fluorine. Quantum yields as high as 50% have been observed from these SF(6) etched Si-NCs despite oxidation.
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Affiliation(s)
- R W Liptak
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
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41
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Li QS, Zhang RQ, Lee ST, Niehaus TA, Frauenheim T. Optimal surface functionalization of silicon quantum dots. J Chem Phys 2008; 128:244714. [DOI: 10.1063/1.2940735] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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42
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Wang BC, Chou YM, Deng JP, Dung YT. Structural and Optical Properties of Passivated Silicon Nanoclusters with Different Shapes: A Theoretical Investigation. J Phys Chem A 2008; 112:6351-7. [DOI: 10.1021/jp8006975] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Bo-Cheng Wang
- Department of Chemistry, Tamkang University, Tamsui 251, Taiwan, and Department of Physics, Chinese Culture University, Taipei 110, Taiwan
| | - Yu-Ma Chou
- Department of Chemistry, Tamkang University, Tamsui 251, Taiwan, and Department of Physics, Chinese Culture University, Taipei 110, Taiwan
| | - Jin-Pei Deng
- Department of Chemistry, Tamkang University, Tamsui 251, Taiwan, and Department of Physics, Chinese Culture University, Taipei 110, Taiwan
| | - Yu-Tsai Dung
- Department of Chemistry, Tamkang University, Tamsui 251, Taiwan, and Department of Physics, Chinese Culture University, Taipei 110, Taiwan
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43
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Zurek E, Autschbach J, Malinowski N, Enders A, Kern K. Experimental and theoretical investigations of the thermodynamic stability of Ba-c(60) and K-C(60) compound clusters. ACS NANO 2008; 2:1000-1014. [PMID: 19206498 DOI: 10.1021/nn800022d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A novel experimental set-up was used to study superstable (magic) Ba-C(60) and K-C(60) compound clusters. The most stable systems observed cannot be rationalized by simple electronic or by geometrical shell filling arguments. Annealing the clusters past the temperature necessary for the fragmentation of the initial metastable clusters formed at the source reveals information about their thermodynamic stability. Higher temperatures yield larger species, suggesting that similar experiments may be used to rationally produce nanoscale clusters with highly desirable properties. Density functional calculations reveal ionic (K, Ba) and covalent (Ba) bonding between C(60) and the metal atoms. The entropic contribution to the Gibbs free energy is shown to be essential in determining absolute and relative cluster stabilities. In particular, we demonstrate that at higher temperatures the entropy favors the formation of larger clusters. A simple criterion which may be used to determine the absolute and relative stabilities of general multicomponent clusters is proposed.
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Affiliation(s)
- Eva Zurek
- Max-Planck-Institut für Festkorperforschung, Heisenbergstrasse 1, 70569, Stuttgart, Germany.
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Choi J, Tung SH, Wang NS, Reipa V. Small-angle neutron scattering measurement of silicon nanoparticle size. NANOTECHNOLOGY 2008; 19:085715. [PMID: 21730746 DOI: 10.1088/0957-4484/19/8/085715] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We have determined the particle size distribution profiles of octane-terminated silicon nanoparticle suspensions, produced using the sonication of electrochemically etched Si wafers. Small-angle neutron scattering data was analyzed separately in high (0.4 nm(-1)<q<3.0 nm(-1)) and low (q<0.4 nm(-1)) scattering vector ranges. Data in the high q range is consistent with the log-normal distribution of isolated spherical particles with median diameter d = 3 ± 0.2 nm. Particle sizes were also indirectly assessed from photoluminescence and optical transmission spectroscopy using the size/bandgap relation: E(g) = 3.44d(-0.5), where E(g) is in eV and d in nm. Both measurements were consistent with the particle size distribution profiles, estimated from ANS data fitting and TEM image analysis. A subpopulation of larger, irregular shape structures in the size range 10-50 nm was also indicated by neutron scattering in the low q range and HRTEM images. However, further studies are warranted to explain a relationship between the slope of scattering intensity versus scattering vector dependence in the intermediate scattering vector range (0.4 nm(-1)<q<1.0 nm(-1)) and the role of non-geometrical Si nanoparticle characteristics (mutual interaction forces, surface termination, etc).
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Affiliation(s)
- Jonghoon Choi
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20742, USA. Biochemical Science Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
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Dickinson FM, Alsop TA, Al-Sharif N, Berger CEM, Datta HK, Šiller L, Chao Y, Tuite EM, Houlton A, Horrocks BR. Dispersions of alkyl-capped silicon nanocrystals in aqueous media: photoluminescence and ageing. Analyst 2008; 133:1573-80. [DOI: 10.1039/b801921e] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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46
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Lehtonen O, Sundholm D, Vänskä T. Computational studies of semiconductor quantum dots. Phys Chem Chem Phys 2008; 10:4535-50. [DOI: 10.1039/b804212h] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Chao Y, Siller L, Krishnamurthy S, Coxon PR, Bangert U, Gass M, Kjeldgaard L, Patole SN, Lie LH, O'Farrell N, Alsop TA, Houlton A, Horrocks BR. Evaporation and deposition of alkyl-capped silicon nanocrystals in ultrahigh vacuum. NATURE NANOTECHNOLOGY 2007; 2:486-489. [PMID: 18654345 DOI: 10.1038/nnano.2007.224] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Accepted: 06/27/2007] [Indexed: 05/26/2023]
Abstract
Nanocrystals are under active investigation because of their interesting size-dependent properties and potential applications. Silicon nanocrystals have been studied for possible uses in optoelectronics, and may be relevant to the understanding of natural processes such as lightning strikes. Gas-phase methods can be used to prepare nanocrystals, and mass spectrometric techniques have been used to analyse Au and CdSe clusters. However, it is difficult to study nanocrystals by such methods unless they are synthesized in the gas phase. In particular, pre-prepared nanocrystals are generally difficult to sublime without decomposition. Here we report the observation that films of alkyl-capped silicon nanocrystals evaporate upon heating in ultrahigh vacuum at 200 degrees C, and the vapour of intact nanocrystals can be collected on a variety of solid substrates. This effect may be useful for the controlled preparation of new quantum-confined silicon structures and could facilitate their mass spectroscopic study and size-selection.
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48
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Giuliani JR, Harley SJ, Carter RS, Power PP, Augustine MP. Using liquid and solid state NMR and photoluminescence to study the synthesis and solubility properties of amine capped silicon nanoparticles. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2007; 32:1-10. [PMID: 17611084 DOI: 10.1016/j.ssnmr.2007.02.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2006] [Accepted: 02/27/2007] [Indexed: 05/16/2023]
Abstract
Water soluble silicon nanoparticles were prepared by the reaction of bromine terminated silicon nanoparticles with 3-(dimethylamino)propyl lithium and characterized with liquid and solid state nuclear magnetic resonance (NMR) and photoluminescence (PL) spectroscopies. The surface site dependent 29Si chemical shifts and the nuclear spin relaxation rates from an assortment of 1H-29Si heteronuclear solid state NMR experiments for the amine coated reaction product are consistent with both the 1H and 13C liquid state NMR results and routine transmission electron microscopy, ultra-violet/visible, and Fourier transform infrared measurements. PL was used to demonstrate the pH dependent solubility properties of the amine passivated silicon nanoparticles.
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Affiliation(s)
- J R Giuliani
- Department of Chemistry, One Shields Avenue, University of California, Davis, CA 95616, USA
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Li QS, Zhang RQ, Niehaus TA, Frauenheim T, Lee ST. Theoretical Studies on Optical and Electronic Properties of Propionic-Acid-Terminated Silicon Quantum Dots. J Chem Theory Comput 2007; 3:1518-26. [DOI: 10.1021/ct700041v] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Q. S. Li
- Centre of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, China, Bremen Center for Computational Material Science, University Bremen, 28334 Bremen, Germany, and Department of Molecular Biophysics, German Cancer Research Center, D-69120 Heidelberg, Germany
| | - R. Q. Zhang
- Centre of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, China, Bremen Center for Computational Material Science, University Bremen, 28334 Bremen, Germany, and Department of Molecular Biophysics, German Cancer Research Center, D-69120 Heidelberg, Germany
| | - T. A. Niehaus
- Centre of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, China, Bremen Center for Computational Material Science, University Bremen, 28334 Bremen, Germany, and Department of Molecular Biophysics, German Cancer Research Center, D-69120 Heidelberg, Germany
| | - Th. Frauenheim
- Centre of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, China, Bremen Center for Computational Material Science, University Bremen, 28334 Bremen, Germany, and Department of Molecular Biophysics, German Cancer Research Center, D-69120 Heidelberg, Germany
| | - S. T. Lee
- Centre of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, China, Bremen Center for Computational Material Science, University Bremen, 28334 Bremen, Germany, and Department of Molecular Biophysics, German Cancer Research Center, D-69120 Heidelberg, Germany
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Choi J, Wang NS, Reipa V. Photoassisted tuning of silicon nanocrystal photoluminescence. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:3388-94. [PMID: 17295527 DOI: 10.1021/la062906+] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Silicon is a rather inefficient light emitter due to the indirect band gap electronic structure, requiring a phonon to balance the electron momentum during the interband transition. Fortunately, momentum requirements are relaxed in the 1-5 nm diameter Si crystals as a result of quantum confinement effects, and bright photoluminescence (PL) in the UV-vis range is achieved. Photoluminescent Si nanocrystals along with the C- and SiC-based nanoparticles are considered bioinert and may lead to the development of biocompatible and smaller probes than the well-known metal chalcogenide-based quantum dots. Published Si nanocrystal production procedures typically do not allow for the fine control of the particle size. An accepted way to make the H-terminated Si nanocrystals consists of anodic Si wafer etching with the subsequent breakup of the porous film in an ultrasound bath. Resulting H-termination provides a useful platform for further chemical derivatization and conjugation to biomolecules. However, a rather polydisperse mixture is produced following the ultrasonic treatment, leading to the distributed band gap energies and the extent of surface passivation. From the technological point of view, a homogeneous nanoparticle size mixture is highly desirable. In this study, we offer an efficient way to reduce the H-terminated Si nanocrystal diameter and narrow size distribution through photocatalyzed dissolution in a HF/HNO3 acid mixture. Si particles were produced using the lateral etching of a Si wafer in a HF/EtOH/H2O bath followed by sonication in deaerated methanol. Initial suspensions exhibited broad photoluminescence in the red spectral region. Photoassisted etching was carried out by adding the HF/HNO3 acid mixture to the suspension and exposing it to a 340 nm light. Photoluminescence and absorbance spectra, measured during dissolution, show the gradual particle size decrease as confirmed by the photoluminescence blue shift. The simultaneous narrowing of the photoluminescence spectral bandwidth suggests that the dissolution rate varies with the particle size. We show that the Si nanoparticle dissolution rate depends on the amount of light adsorbed by the particle and accounts for the etching rate variation with the particle size. Significant improvement in the PL quantum yield is observed during the acid treatment, suggesting improvement in the dangling bond passivation.
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Affiliation(s)
- Jonghoon Choi
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, MD 20742, USA
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