1
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Funston AM, Hemmer E, Chowdhury A, Veinot JGC. Introduction to fundamental processes in optical nanomaterials. Nanoscale 2024; 16:8193-8195. [PMID: 38644745 DOI: 10.1039/d4nr90078b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
An introduction to the joint Nanoscale and Chemical Communications (ChemComm) themed collection focused on fundamental processes in optical nanomaterials that features a series of articles describing the properties of this versatile class of materials while highlighting some of their potential applications.
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Affiliation(s)
- Alison M Funston
- ARC Centre of Excellence in Exciton Science, Monash University, Clayton, Victoria 3800, Australia.
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Eva Hemmer
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON, Canada.
| | - Arindam Chowdhury
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
| | - Jonathan G C Veinot
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
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2
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Yuan G, Higginbotham HF, Han J, Yadav A, Kirkwood N, Mulvaney P, Bell TDM, Cole JH, Funston AM. Tuning the Photoluminescence Anisotropy of Semiconductor Nanocrystals. ACS Nano 2023; 17:19109-19120. [PMID: 37748102 DOI: 10.1021/acsnano.3c05214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/27/2023]
Abstract
Semiconductor nanocrystals are promising optoelectronic materials. Understanding their anisotropic photoluminescence is fundamental for developing quantum-dot-based devices such as light-emitting diodes, solar cells, and polarized single-photon sources. In this study, we experimentally and theoretically investigate the photoluminescence anisotropy of CdSe semiconductor nanocrystals with various shapes, including plates, rods, and spheres, with either wurtzite or zincblende structures. We use defocused wide-field microscopy to visualize the emission dipole orientation and find that spheres, rods, and plates exhibit the optical properties of 2D, 1D, and 2D emission dipoles, respectively. We rationalize the seemingly counterintuitive observation that despite having similar aspect ratios (width/length), rods and long nanoplatelets exhibit different defocused emission patterns by considering valence band structures calculated using multiband effective mass theory and the dielectric effect. The principles are extended to provide general relationships that can be used to tune the emission dipole orientation for different materials, crystalline structures, and shapes.
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Affiliation(s)
- Gangcheng Yuan
- ARC Centre of Excellence in Exciton Science, Monash University, Clayton, Victoria 3800, Australia
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | | | - Jiho Han
- ARC Centre of Excellence in Exciton Science, School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Anchal Yadav
- ARC Centre of Excellence in Exciton Science, Monash University, Clayton, Victoria 3800, Australia
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Nicholas Kirkwood
- ARC Centre of Excellence in Exciton Science, School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Paul Mulvaney
- ARC Centre of Excellence in Exciton Science, School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Toby D M Bell
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Jared H Cole
- ARC Centre of Excellence in Exciton Science and Chemical and Quantum Physics, School of Science, RMIT University, Melbourne, 3001, Australia
| | - Alison M Funston
- ARC Centre of Excellence in Exciton Science, Monash University, Clayton, Victoria 3800, Australia
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
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3
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Liu ACY, Davis TJ, Coenen T, Hari S, Voortman LM, Xu Z, Yuan G, Ballard PM, Funston AM, Etheridge J. Modulation of Cathodoluminescence by Surface Plasmons in Silver Nanowires. Small 2023; 19:e2207747. [PMID: 37029699 DOI: 10.1002/smll.202207747] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 02/08/2023] [Indexed: 06/19/2023]
Abstract
The waveguide modes in chemically-grown silver nanowires on silicon nitride substrates are observed using spectrally- and spatially-resolved cathodoluminescence (CL) excited by high-energy electrons in a scanning electron microscope. The presence of a long-range, travelling surface plasmon mode modulates the coupling efficiency of the incident electron energy into the nanowires, which is observed as oscillations in the measured CL with the point of excitation by the focused electron beam. The experimental data are modeled using the theory of surface plasmon polariton modes in cylindrical metal waveguides, enabling the complex mode wavenumbers and excitation strength of the long-range surface plasmon mode to be extracted. The experiments yield insight into the energy transfer mechanisms between fast electrons and coherent oscillations in surface charge density in metal nanowires and the relative amplitudes of the radiative processes excited in the wire by the electron.
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Affiliation(s)
- Amelia C Y Liu
- School of Physics and Astronomy, Monash University, Clayton, Victoria, 3800, Australia
- Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria, 3800, Australia
| | - Timothy J Davis
- School of Physics, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Toon Coenen
- Delmic BV, Kanaalweg 4, Delft, 2628 EB, The Netherlands
| | | | - Lenard M Voortman
- Delmic BV, Kanaalweg 4, Delft, 2628 EB, The Netherlands
- Division of Cell and Chemical Biology, Leiden University Medical Centre, Leiden University, Leiden, 2333 ZC, The Netherlands
| | - Zhou Xu
- Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria, 3800, Australia
| | - Gangcheng Yuan
- ARC Centre of Excellence in Exciton Science and School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | - Patrycja M Ballard
- ARC Centre of Excellence in Exciton Science and School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | - Alison M Funston
- ARC Centre of Excellence in Exciton Science and School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | - Joanne Etheridge
- School of Physics and Astronomy, Monash University, Clayton, Victoria, 3800, Australia
- Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria, 3800, Australia
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
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4
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Hargreaves R, Duwé S, Rozario AM, Funston AM, Tabor RF, Dedecker P, Whelan DR, Bell TDM. Live-Cell SOFI Correlation with SMLM and AFM Imaging. ACS Bio Med Chem Au 2023; 3:261-269. [PMID: 37363082 PMCID: PMC10288496 DOI: 10.1021/acsbiomedchemau.2c00086] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/09/2023] [Accepted: 03/10/2023] [Indexed: 06/28/2023]
Abstract
Standard optical imaging is diffraction-limited and lacks the resolving power to visualize many of the organelles and proteins found within the cell. The advent of super-resolution techniques overcame this barrier, enabling observation of subcellular structures down to tens of nanometers in size; however these techniques require or are typically applied to fixed samples. This raises the question of how well a fixed-cell image represents the system prior to fixation. Here we present the addition of live-cell Super-Resolution Optical Fluctuation Imaging (SOFI) to a previously reported correlative process using Single Molecule Localization Microscopy (SMLM) and Atomic Force Microscopy (AFM). SOFI was used with fluorescent proteins and low laser power to observe cellular ultrastructure in live COS-7 cells. SOFI-SMLM-AFM of microtubules showed minimal changes to the microtubule network in the 20 min between live-cell SOFI and fixation. Microtubule diameters were also analyzed through all microscopies; SOFI found diameters of 249 ± 68 nm and SMLM was 71 ± 33 nm. AFM height measurements found microtubules to protrude 26 ± 13 nm above the surrounding cellular material. The correlation of SMLM and AFM was extended to two-color SMLM to image both microtubules and actin. Two target SOFI was performed with various fluorescent protein combinations. rsGreen1-rsKAME, rsGreen1-Dronpa, and ffDronpaF-rsKAME fluorescent protein combinations were determined to be suitable for two target SOFI imaging. This correlative application of super-resolution live-cell and fixed-cell imaging revealed minimal artifacts created for the imaged target structures through the sample preparation procedure and emphasizes the power of correlative microscopy.
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Affiliation(s)
| | - Sam Duwé
- Advanced
Optical Microscopy Centre, Hasselt University, Diepenbeek 3590, Belgium
| | - Ashley M. Rozario
- Department
of Rural Clinical Sciences, La Trobe Institute for Molecular Science, La Trobe University, Bendigo 3552, Victoria, Australia
| | - Alison M. Funston
- School
of Chemistry, Monash University, Melbourne, Victoria 3800, Australia
- ARC
Centre of Excellence in Exciton Science, Monash University, Clayton, Victoria 3800, Australia
| | - Rico F. Tabor
- School
of Chemistry, Monash University, Melbourne, Victoria 3800, Australia
| | - Peter Dedecker
- Department
of Chemistry, KU Leuven, Leuven 3001, Belgium
| | - Donna R. Whelan
- Department
of Rural Clinical Sciences, La Trobe Institute for Molecular Science, La Trobe University, Bendigo 3552, Victoria, Australia
| | - Toby D. M. Bell
- School
of Chemistry, Monash University, Melbourne, Victoria 3800, Australia
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5
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Pal R, Sikder AK, Saito K, Funston AM, Bellare JR. Study of polycarbonate‐polystyrene interfaces using Scanning Transmission Electron
Microscopy‐Spectrum
Imaging (
STEM‐SI
). POLYM INT 2022. [DOI: 10.1002/pi.6451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ruchi Pal
- IITB‐Monash Research Academy IIT Bombay Mumbai 400076 India
| | - Arun K. Sikder
- SABIC Research and Technology Pvt. Ltd. Bengaluru 562125 India
| | - Kei Saito
- School of Chemistry, Monash University Clayton Victoria 3800 Australia
| | - Alison M. Funston
- School of Chemistry, Monash University Clayton Victoria 3800 Australia
- ARC Centre of Excellence in Exciton Science, School of Chemistry Monash University Clayton Victoria 3800 Australia
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6
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Li H, Yin W, Ng CK, Huang R, Du S, Sharma M, Li B, Yuan G, Michalska M, Matta SK, Chen Y, Chandrasekaran N, Russo S, Cameron NR, Funston AM, Jasieniak JJ. Macroporous perovskite nanocrystal composites for ultrasensitive copper ion detection. Nanoscale 2022; 14:11953-11962. [PMID: 35899800 DOI: 10.1039/d2nr02737b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Accumulation of heavy metal ions, including copper ions (Cu2+), presents a serious threat to human health and to the environment. A substantial amount of research has focused on detecting such species in aqueous solutions. However, progress towards ultrasensitive and easy-to-use sensors for non-aqueous solutions is still limited. Here, we focus on the detection of copper species in hexane, realising ultra-sensitive detection through a fluorescence-based approach. To achieve this, a novel macroporous composite material has been developed featuring luminescent CsPbBr3 nanocrystals (NCs) chemically adhered to a polymerized high internal phase emulsion (polyHIPE) substrate through surface thiol groups. Due to this thiol functionality, sub-monolayer NC formation is realised, which also renders outstanding stability of the composite in the ambient environment. Copper detection is achieved through a direct solution based immersion of the CsPbBr3-(SH)polyHIPE composite, which results in concentration-dependent quenching of the NC photoluminescence. This newly developed sensor has a limit of detection (LOD) for copper as low as 1 × 10-16 M, and a wide operating window spanning 10-2 to 10-16 M. Moreover, the composite exhibits excellent selectivity among different transition metals.
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Affiliation(s)
- Hanchen Li
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Wenping Yin
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Chun Kiu Ng
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Ruoxi Huang
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Shengrong Du
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Manoj Sharma
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Bin Li
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Gangcheng Yuan
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | - Monika Michalska
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Sri Kasi Matta
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- School of Science, RMIT University, Melbourne, 3000, Australia
| | - Yu Chen
- Monash Centre for Electron Microscopy (MCEM), Monash University, Clayton, Victoria, 3800, Australia
| | - Naresh Chandrasekaran
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - Salvy Russo
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- School of Science, RMIT University, Melbourne, 3000, Australia
| | - Neil R Cameron
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
- School of Engineering, University of Warwick, Coventry CV4 7AL, U.K
| | - Alison M Funston
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | - Jacek J Jasieniak
- Australian Research Council Centre of Excellence in Exciton Science, Australia.
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
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7
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Hargreaves RB, Rozario AM, McCoy TM, Meaney SP, Funston AM, Tabor RF, Whelan DR, Bell TD. Optimising correlative super resolution and atomic force microscopies for investigating the cellular cytoskeleton. Methods Appl Fluoresc 2022; 10. [DOI: 10.1088/2050-6120/ac8526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 07/28/2022] [Indexed: 11/12/2022]
Abstract
Abstract
Correlative imaging methods can provide greater information for investigations of cellular ultra-structure, with separate analysis methods complementing each other’s strengths and covering for deficiencies. Here we present a method for correlative applications of super resolution and atomic force microscopies, optimising the sample preparation for correlative imaging of the cellular cytoskeleton in COS-7 cells. This optimisation determined the order of permeabilisation and fixation, the concentration of Triton X-100 surfactant used and time required for sufficient removal of the cellular membrane while maintaining the microtubule network. Correlative SMLM/AFM imaging revealed the different information that can be obtained through each microscopy. The widths of microtubules and microtubule clusters were determined from both AFM height measurements and Gaussian fitting of SMLM intensity cross sections, these were then compared to determine the orientation of microtubules within larger microtubule bundles. The ordering of microtubules at intersections was determined from the AFM height profiles as each microtubule crosses the other. The combination of both microtubule diameter measurements enabled greater information on their structure to be found than either measurement could individually.
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8
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Frazer L, Mercier TM, Krishnan C, Xu Z, Liu ACY, Yuan G, Kong J, Lagoudakis PG, Charlton MDB, Funston AM. Quasiperiodic light. Opt Lett 2022; 47:3556-3559. [PMID: 35838729 DOI: 10.1364/ol.461613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 06/26/2022] [Indexed: 06/15/2023]
Abstract
Quasiperiodicity is a form of spatial order that has been observed in quasicrystalline matter but not light. We construct a quasicrystalline surface out of a light emitting diode. Using a nanoscale waveguide as a microscope (NSOM), we directly image the light field at the surface of the diode. Here we show, using reciprocal space representations of the images, that the light field is quasiperiodic. We explain the structure of the light field with wave superposition. Periodic ordering is limited to at most six-fold symmetry. The light field exhibits 12-fold quasisymmetry, showing order while disproving periodicity. This demonstrates that a new class, consisting of projections from hyperspace, exists in the taxonomy of light ordering.
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9
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Pal R, Bourgeois L, Weyland M, Sikder AK, Saito K, Funston AM, Bellare JR. Chemical Fingerprinting of Polymers Using Electron Energy-Loss Spectroscopy. ACS Omega 2021; 6:23934-23942. [PMID: 34568672 PMCID: PMC8459415 DOI: 10.1021/acsomega.1c02939] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Indexed: 06/13/2023]
Abstract
Electron energy-loss spectroscopy (EELS) is becoming an important tool in the characterization of polymeric materials. The sensitivity of EELS to changes in the chemical structure of polymeric materials dictates its applicability. In particular, it is important for compositional analysis to have reference spectra of pure components. Here, we report the spectra of the carbon K-edge of six polymers (polyethylene, polypropylene, polybutylene terephthalate, and polylactic acid) including copolymers (styrene acrylonitrile and acrylonitrile butadiene styrene), to be used as reference spectra for future EELS studies of polymers. We have successfully decomposed the carbon K-edge of each of the polymers and assigned the observed peaks to bonding transitions. The spectra have been acquired in standard experimental conditions, and electron beam damage has been taken into account during establishment of spectral-structural relationships. We found that the more commonly available low-energy resolution spectrometers are adequate to chemically fingerprint linear saturated hydrocarbons such as PE, PP, and PLA. We have thus moved a step closer toward creating an atlas of polymer EELS spectra, which can be subsequently used for chemical bond mapping of polymeric materials with nanoscale spatial resolution.
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Affiliation(s)
- Ruchi Pal
- IITB-Monash
Research Academy, IIT Bombay, Mumbai 400076, India
| | - Laure Bourgeois
- Monash
Centre for Electron Microscopy, Monash University, Clayton, Victoria 3800, Australia
- Department
of Materials Science & Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Matthew Weyland
- Monash
Centre for Electron Microscopy, Monash University, Clayton, Victoria 3800, Australia
- Department
of Materials Science & Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Arun K. Sikder
- SABIC
Research and Technology Pvt. Ltd., Bengaluru 562125, India
| | - Kei Saito
- School
of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Alison M. Funston
- School
of Chemistry, Monash University, Clayton, Victoria 3800, Australia
- ARC Centre
of Excellence in Exciton Science, School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Jayesh R. Bellare
- Department
of Chemical Engineering, IIT Bombay, Mumbai 400076, India
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10
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Li W, Esser BD, Yadav A, Funston AM, Findlay SD, Zheng C, Etheridge J. Direct imaging of metal additives on Au nanocube surface using 4D-STEM. Acta Crystallogr A Found Adv 2021. [DOI: 10.1107/s0108767321094435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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11
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Esser BD, Funston AM, Etheridge J. Investigating nanoparticle surface energetics using 4D-STEM. Acta Crystallogr A Found Adv 2021. [DOI: 10.1107/s0108767321087535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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12
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Sherrie B, Funston AM, Frazer L. Optimal quantum dot size for photovoltaics with fusion. Nanoscale 2020; 12:24362-24367. [PMID: 33313628 DOI: 10.1039/d0nr07061k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Light fusion increases the efficiency of solar cells by converting photons with lower energy than the bandgap into higher energy photons. The solar cell converts the product photons to current. We use Monte Carlo simulation to predict that lead sulfide (PbS) quantum dot sensitizers will enable fusion with a figure of merit on the mA cm-2 scale, exceeding current records, while enabling silicon cell compatibility. Performance is highly sensitive to quantum dot size, on the order of mA cm-2 nm-1.
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Affiliation(s)
- Benedicta Sherrie
- ARC Centre of Excellence in Exciton Science and School of Chemistry, Monash University, 17 Rainforest Walk, Clayton, VIC 3800, Australia.
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13
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Pal R, Bourgeois L, Weyland M, Sikder AK, Saito K, Funston AM, Bellare JR. Chemical fingerprinting of polyvinyl acetate and polycarbonate using electron energy-loss spectroscopy. Polym Chem 2020. [DOI: 10.1039/d0py00771d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work demonstrates that the high sensitivity of EELS can be used to identify the changes in the chemical structure of polymeric materials.
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Affiliation(s)
- Ruchi Pal
- IITB-Monash Research Academy
- IIT Bombay
- Mumbai 400076
- India
| | - Laure Bourgeois
- Monash Centre for Electron Microscopy
- Monash University
- Australia
- Department of Materials Science & Engineering
- Monash University
| | - Matthew Weyland
- Monash Centre for Electron Microscopy
- Monash University
- Australia
- Department of Materials Science & Engineering
- Monash University
| | - Arun K. Sikder
- SABIC Research and Technology Pvt. Ltd
- Bengaluru 562125
- India
| | - Kei Saito
- School of Chemistry
- Monash University
- Clayton
- Australia
| | - Alison M. Funston
- School of Chemistry
- Monash University
- Clayton
- Australia
- ARC Centre of Excellence in Exciton Science
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14
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Wang C, Chesman ASR, Yin W, Frazer L, Funston AM, Jasieniak JJ. Facile purification of CsPbX 3 (X = Cl -, Br -, I -) perovskite nanocrystals. J Chem Phys 2019; 151:121105. [PMID: 31575186 DOI: 10.1063/1.5123306] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
CsPbI3 perovskite nanocrystals are a promising optoelectronic material when stabilized in their cubic phase. While ongoing efforts have addressed this structural challenge through a variety of meta-stabilization approaches, the postsynthesis purification of these nanocrystal dispersions has remained a challenge. In this article, we undertake a detailed investigation into the chemical, optical, and structural changes that arise during purification of CsPbI3 nanocrystals. It is found that nanocrystal degradation can only be avoided through the judicious control of additives within each purification cycle. Under optimized additive-to-nanocrystal ratios, multiple purification cycles can be readily achieved, while retaining the quality and phase stability of the CsPbI3. This facile purification protocol ensures the preparation of high purity and high quality CsPbI3 nanocrystal inks that are suitable for better characterization or integration in optoelectronic devices. The approach has been generalized for CsPbX3 (X = Cl-, Br-, and I-).
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Affiliation(s)
- Chujie Wang
- ARC Centre of Excellence in Exciton Science, Department of Materials Science and Engineering, Faculty of Engineering, Monash University, Clayton, VIC 3800, Australia
| | - Anthony S R Chesman
- CSIRO Manufacturing, Ian Wark Laboratories, Bayview Ave., Clayton, VIC 3168, Australia
| | - Wenping Yin
- ARC Centre of Excellence in Exciton Science, Department of Materials Science and Engineering, Faculty of Engineering, Monash University, Clayton, VIC 3800, Australia
| | - Laszlo Frazer
- ARC Centre of Excellence in Exciton Science, School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Alison M Funston
- ARC Centre of Excellence in Exciton Science, School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | - Jacek J Jasieniak
- ARC Centre of Excellence in Exciton Science, Department of Materials Science and Engineering, Faculty of Engineering, Monash University, Clayton, VIC 3800, Australia
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15
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Abstract
Developments in DNA nanotechnology offer control of the self-assembly of materials into discrete nanostructures. Within this paradigm, pre-assembled DNA origami with hundreds of DNA strands allows for precise and programmable spatial positioning of functionalised nanoparticles. We propose an alternative approach to construct multiple, structurally different, nanoparticle assemblies from just a few complementary nanoparticle-functionalised DNA strands. The approach exploits local minima in the potential energy landscape of hybridised nanoparticle-DNA structures by employing kinetic control of the assembly. Using a four-strand DNA template, we synthesise five different 3D gold nanoparticle (plasmonic) tetrameric isomers, akin to molecular structural isomers. The number of different structures formed using this approach for a set of DNA strands represents a combinatorial library, which we summarise in a hybridisation pathway tree and use to achieve deposition of tetrahedral assemblies onto substrates in high yield. The ability to program nanoparticle self-assembly pathways gives unprecedented access to unique plasmonic nanostructures.
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Affiliation(s)
- Laurent Lermusiaux
- ARC Centre of Excellence in Exciton Science and School of Chemistry, Monash University, Clayton, VIC 3800, Australia.
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16
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Mayevsky AD, Davis TJ, Ballard PM, Henderson CA, Funston AM. Mesoscale surface plasmons: modelling and imaging using near-field scanning optical microscopy. Opt Express 2018; 26:23426-23435. [PMID: 30184843 DOI: 10.1364/oe.26.023426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 08/09/2018] [Indexed: 06/08/2023]
Abstract
Meso-scale plasmons are supported by structures with dimensions on the order of tens of plasmon wavelengths. Metal structures at this length-scale are promising for the design and engineering of structures to direct the flow of optical energy and generate high intensity, localized electric fields. The near-field optical properties of mesoscale crystalline gold plates were examined using near-field scanning optical microscopy with a focus on the effects of modifying morphology and excitation conditions. Excitation of surface plasmon polaritons (SPPs) at plate edges and their subsequent propagation and interference as radial waves across the surface results in nodes of enhancement of the near-field on the plate surface at specific positions within the plate. The spatial position of the near-field enhancement may be directed by controlling either, or both, the boundary conditions (plate shape) and polarization of the excitation light.
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17
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Tong W, Katz-Boon H, Walsh MJ, Weyland M, Etheridge J, Funston AM. The evolution of size, shape, and surface morphology of gold nanorods. Chem Commun (Camb) 2018; 54:3022-3025. [PMID: 29511759 DOI: 10.1039/c7cc08336j] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We investigate the transformation of single crystal gold nanorod surface morphology over extended growth times. After initial rapid anisotropic growth and disappearance of {111} bridging facets, the aspect ratios converge across AgNO3 concentrations. The surface morphology transitions from faceted to curved. These observations imply the final aspect ratio has little dependence on the AgNO3 concentration, consistent with primary control of the AgNO3 over aspect ratio occurring at the symmetry breaking point.
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Affiliation(s)
- Wenming Tong
- ARC Centre of Excellence in Exciton Science and School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.
| | - Hadas Katz-Boon
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Michael J Walsh
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Matthew Weyland
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia and Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria 3800, Australia
| | - Joanne Etheridge
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia and Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria 3800, Australia
| | - Alison M Funston
- ARC Centre of Excellence in Exciton Science and School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.
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18
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Cook AR, Valášek M, Funston AM, Poliakov P, Michl J, Miller JR. p-Carborane Conjugation in Radical Anions of Cage–Cage and Cage–Phenyl Compounds. J Phys Chem A 2018; 122:798-810. [DOI: 10.1021/acs.jpca.7b10885] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrew R. Cook
- Chemistry
Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Michal Valášek
- Institute
of Organic Chemistry and Biochemistry, ASCR, Prague 6 16610, Czech Republic
| | - Alison M. Funston
- Chemistry
Department, Brookhaven National Laboratory, Upton, New York 11973, United States
- School
of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Pavel Poliakov
- Chemistry
Department, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Josef Michl
- Institute
of Organic Chemistry and Biochemistry, ASCR, Prague 6 16610, Czech Republic
- Department
of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - John R. Miller
- Chemistry
Department, Brookhaven National Laboratory, Upton, New York 11973, United States
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19
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Walsh MJ, Tong W, Katz-Boon H, Mulvaney P, Etheridge J, Funston AM. A Mechanism for Symmetry Breaking and Shape Control in Single-Crystal Gold Nanorods. Acc Chem Res 2017; 50:2925-2935. [PMID: 29144733 DOI: 10.1021/acs.accounts.7b00313] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The phenomenon of symmetry breaking-in which the order of symmetry of a system is reduced despite manifest higher-order symmetry in the underlying fundamental laws-is pervasive throughout science and nature, playing a critical role in fields ranging from particle physics and quantum theory to cosmology and general relativity. For the growth of crystals, symmetry breaking is the crucial step required to generate a macroscopic shape that has fewer symmetry elements than the unit cell and/or seed crystal from which it grew. Advances in colloid synthesis have enabled a wide variety of nanocrystal morphologies to be achieved, albeit empirically. Of the various nanoparticle morphologies synthesized, gold nanorods have perhaps been the most intensely studied, thanks largely to their unique morphology-dependent optical properties and exciting application potential. However, despite intense research efforts, an understanding of the mechanism by which a single crystal breaks symmetry and grows anisotropically has remained elusive, with many reports presenting seemingly conflicting data and theories. A fundamental understanding of the symmetry breaking process is needed to provide a rational framework upon which future synthetic approaches can be built. Inspired by recent experimental results and drawing upon the wider literature, we present a mechanism for gold nanorod growth from the moments prior to symmetry breaking to the final product. In particular, we describe the steps by which a cuboctahedral seed particle breaks symmetry and undergoes anisotropic growth to form a nanorod. With an emphasis on the evolving crystal structure, we highlight the key geometrical and chemical drivers behind the symmetry breaking process and factors that govern the formation and growth of nanorods, including control over the crystal width, length, and surface faceting. We propose that symmetry breaking is induced by an initial formation of a new surface structure that is stabilized by the deposition of silver, thus preserving this facet in the embryonic nanorod. These new surfaces initially form stochastically as truncations that remove high-energy edge atoms at the intersection of existing {111} facets and represent the beginnings of a {011}-type surface. Crucially, the finely tuned [HAuCl4]:[AgNO3] ratio and reduction potential of the system mean that silver deposition can occur on the more atomically open surface but not on the pre-existing lower-index facets. The stabilized surfaces develop into side facets of the nascent nanorod, while the largely unpassivated {111} facets are the predominant site of Au atom deposition. Growth in the width direction is tightly controlled by a self-sustaining cycle of galvanic replacement and silver deposition. It is the [HAuCl4]:[AgNO3] ratio that directly determines the particle size at which the more open atomic surfaces can be stabilized by silver and the rate of growth in the width direction following symmetry breaking, thus explaining the known aspect ratio control with Ag ion concentration. We describe the evolving surface faceting of the nanorod and the emergence of higher-index facets. Collectively, these observations allow us to identify facet-size and edge-atom effects as a simple fundamental driver of symmetry breaking and the subsequent development of new surfaces in the presence of adsorbates.
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Affiliation(s)
| | | | | | - Paul Mulvaney
- ARC
Centre of Excellence in Exciton Science, School of Chemistry, and
Bio21 Institute, University of Melbourne, Parkville, Victoria 3010, Australia
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20
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Zhu Y, Nakashima PNH, Funston AM, Bourgeois L, Etheridge J. Topologically Enclosed Aluminum Voids as Plasmonic Nanostructures. ACS Nano 2017; 11:11383-11392. [PMID: 29094925 DOI: 10.1021/acsnano.7b05944] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Recent advances in the ability to synthesize metallic nanoparticles with tailored geometries have led to a revolution in the field of plasmonics. However, studies of the important complementary system, an inverted nanostructure, have so far been limited to two-dimensional sphere-segment voids or holes. Here we reveal the localized surface plasmon resonances (LSPRs) of nanovoids that are topologically enclosed in three-dimensions: an "anti-nanoparticle". We combine this topology with the favorable plasmonic properties of aluminum to observe strongly localized field enhancements with LSPR energies in the extreme UV range, well beyond those accessible with noble metals or yet achieved with aluminum. We demonstrate the resonance tunability by tailoring the shape and size of the nanovoids, which are truncated octahedra in the 10-20 nm range. This system is pristine: the nanovoid cavity is free from any oxide or supporting substrate that would affect the LSPRs. We exploit this to infer LSPRs of pure, sub-20-nm Al nanoparticles, which have yet to be synthesized. Access to this extreme UV range will allow applications in LSPR-enhanced UV photoemission spectroscopy and photoionization.
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Affiliation(s)
- Ye Zhu
- Department of Materials Science and Engineering, Monash University , Melbourne, VIC 3800, Australia
- Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Kowloon, Hong Kong, People's Republic of China
| | - Philip N H Nakashima
- Department of Materials Science and Engineering, Monash University , Melbourne, VIC 3800, Australia
| | - Alison M Funston
- ARC Centre of Excellence in Exciton Science, School of Chemistry, Monash University , Melbourne, VIC 3800, Australia
| | - Laure Bourgeois
- Department of Materials Science and Engineering, Monash University , Melbourne, VIC 3800, Australia
- Monash Centre for Electron Microscopy, Monash University , Melbourne, VIC 3800, Australia
| | - Joanne Etheridge
- Department of Materials Science and Engineering, Monash University , Melbourne, VIC 3800, Australia
- Monash Centre for Electron Microscopy, Monash University , Melbourne, VIC 3800, Australia
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21
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Abstract
Electron energy loss spectroscopy (EELS) allows imaging as well as extraction of spatially resolved chemical information and this review presents how EELS can be ap plied to polymeric systems.
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Affiliation(s)
- Ruchi Pal
- IITB-Monash Research Academy
- IIT Bombay
- Mumbai 400076
- India
| | - Arun K. Sikder
- SABIC Research and Technology Pvt. Ltd
- Bangalore 562125
- India
| | - Kei Saito
- School of Chemistry
- Monash University
- Clayton
- Australia
| | - Alison M. Funston
- School of Chemistry
- Monash University
- Clayton
- Australia
- ARC Centre of Excellence in Exciton Science
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22
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Abstract
A reliable and reproducible method to rapidly charge single gold nanocrystals in a solid-state device is reported. Gold nanorods (Au NRs) were integrated into an ion gel capacitor, enabling them to be charged in a transparent and highly capacitive device, ideal for optical transmission. Changes in the electron concentration of a single Au NR were observed with dark-field imaging spectroscopy via localized surface plasmon resonance (LSPR) shifts in the scattering spectrum. A time-resolved, laser-illuminated, dark-field system was developed to enable direct measurement of single particle charging rates with time resolution below one millisecond. The added sensitivity of this new approach has enabled the optical detection of fewer than 110 electrons on a single Au NR. Single wavelength resonance shifts provide a much faster, more sensitive method for all surface plasmon-based sensing applications.
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Affiliation(s)
| | - Xingzhan Wei
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences , Chongqing, 400714, China
| | | | - Alison M Funston
- School of Chemistry, Monash University , Clayton, Victoria 3800, Australia
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23
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Barrow SJ, Collins SM, Rossouw D, Funston AM, Botton GA, Midgley PA, Mulvaney P. Electron Energy Loss Spectroscopy Investigation into Symmetry in Gold Trimer and Tetramer Plasmonic Nanoparticle Structures. ACS Nano 2016; 10:8552-63. [PMID: 27482623 DOI: 10.1021/acsnano.6b03796] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We present a combined scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS) investigation into the mode symmetries of plasmonic nanoparticle trimer and tetramer structures. We obtain nanometer-resolved energy loss spectra for both trimer and tetramer structures and compare these to boundary element method simulations. We show that EELS, in conjunction with eigenmode simulations, offers a complete characterization of the individual superstructures, and we trace the evolution of both optically dark and bright modes and identify multipolar mode contributions. We then apply this technique to tetramer structures that exhibit an expanded range of mode symmetries for two-dimensional and three-dimensional self-assembled geometries. These findings provide a comprehensive experimental account of the available photonic states in self-assembled nanoparticle clusters.
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Affiliation(s)
- Steven J Barrow
- School of Chemistry and Bio21 Institute, University of Melbourne , Parkville, Victoria 3010, Australia
| | - Sean M Collins
- Department of Materials Science and Metallurgy, University of Cambridge , 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
| | - David Rossouw
- Materials Science and Engineering, McMaster University , Hamilton, Ontario L8S 4L8, Canada
| | - Alison M Funston
- Chemistry Department, Monash University , Clayton, Victoria 3800, Australia
| | - Gianluigi A Botton
- Materials Science and Engineering, McMaster University , Hamilton, Ontario L8S 4L8, Canada
| | - Paul A Midgley
- Department of Materials Science and Metallurgy, University of Cambridge , 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
| | - Paul Mulvaney
- School of Chemistry and Bio21 Institute, University of Melbourne , Parkville, Victoria 3010, Australia
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24
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Perera CS, Funston AM, Cheng HH, Vernon KC. Mapping bound plasmon propagation on a nanoscale stripe waveguide using quantum dots: influence of spacer layer thickness. Beilstein J Nanotechnol 2015; 6:2046-2051. [PMID: 26665075 PMCID: PMC4660917 DOI: 10.3762/bjnano.6.208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/24/2015] [Indexed: 06/05/2023]
Abstract
In this paper we image the highly confined long range plasmons of a nanoscale metal stripe waveguide using quantum emitters. Plasmons were excited using a highly focused 633 nm laser beam and a specially designed grating structure to provide stronger incoupling to the desired mode. A homogeneous thin layer of quantum dots was used to image the near field intensity of the propagating plasmons on the waveguide. We observed that the photoluminescence is quenched when the QD to metal surface distance is less than 10 nm. The optimised spacer layer thickness for the stripe waveguides was found to be around 20 nm. Authors believe that the findings of this paper prove beneficial for the development of plasmonic devices utilising stripe waveguides.
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Affiliation(s)
| | - Alison M Funston
- School of Chemistry, Monash University, Clayton 3800, VIC, Australia
| | - Han-Hao Cheng
- Australian National Fabrication Facility-QLD Node, AIBN, University of Queensland, St. Lucia 4072, QLD, Australia
| | - Kristy C Vernon
- Queensland University of Technology, Brisbane 4001, QLD, Australia
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25
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Perera CS, Vernon KC, Funston AM, Cheng H, Eftekhari F, Davis TJ. Excitation of bound plasmons along nanoscale stripe waveguides: a comparison of end and grating coupling techniques. Opt Express 2015; 23:10188-10197. [PMID: 25969061 DOI: 10.1364/oe.23.010188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this paper we excite bound long range stripe plasmon modes with a highly focused laser beam. We demonstrate highly confined plasmons propagating along a 50 µm long silver stripe 750 nm wide and 30 nm thick. Two excitation techniques were studied: focusing the laser spot onto the waveguide end and focusing the laser spot onto a silver grating. By comparing the intensity of the out-coupling photons at the end of the stripe for both grating and end excitation we are able to show that gratings provide an increase of a factor of two in the output intensity and thus out-coupling of plasmons excited by this technique are easier to detect. Authors expect that the outcome of this paper will prove beneficial for the development of passive nano-optical devices based on stripe waveguides, by providing insight into the different excitation techniques available and the advantages of each technique.
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26
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Abstract
Metal nanocrystals can be grown in a variety of shapes through the modification of surface facet energies via surfactants. However, the surface facets are only a few atoms wide, making it extremely challenging to measure their geometries and energies. Here, we locate and count atoms in Au nanorods at successive time intervals using quantitative scanning transmission electron microscopy. This enables us to determine the atomic-level geometry and the relative stability of the facets and to expound their relationship to the overall three-dimensional nanocrystal shape and size. We reveal coexisting high- and low-index facets with comparable stability and dimensions and find the geometry of the nanorods is remarkably stable, despite significant atom movements. This information provides unique insights into the mechanisms that govern growth kinetics and nanocrystal morphology.
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Affiliation(s)
- Hadas Katz-Boon
- Department of Materials Engineering, Monash University , Clayton, Victoria 3800, Australia
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27
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Abstract
Formation of anisotropic nanocrystals from isotropic single-crystal precursors requires an essential symmetry breaking event. Single-crystal gold nanorods have become the model system for investigating the synthesis of anisotropic nanoparticles, and their growth mechanism continues to be the subject of intense investigation. Despite this, very little is known about the symmetry breaking event that precedes shape anisotropy. In particular, there remains limited understanding of how an isotropic seed particle becomes asymmetric and of the growth parameters that trigger and drive this process. Here, we present direct atomic-scale observations of the nanocrystal structure at the embryonic stages of gold nanorod growth. The onset of asymmetry of the nascent crystals is observed to occur only for single-crystal particles that have reached diameters of 4-6 nm and only in the presence of silver ions. In this size range, small, asymmetric truncating surfaces with an open atomic structure become apparent. Furthermore, {111} twin planes are observed in some immature nanorods within 1-3 monolayers of the surface. These results provide direct observation of the structural changes that break the symmetry of isotropic nascent nanocrystals and ultimately enable the growth of asymmetric nanocrystals.
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Affiliation(s)
- Michael J Walsh
- Department of Materials Engineering, ‡School of Chemistry, and §Monash Centre for Electron Microscopy, Monash University , VIC, 3800, Australia
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28
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Barrow SJ, Rossouw D, Funston AM, Botton GA, Mulvaney P. Mapping bright and dark modes in gold nanoparticle chains using electron energy loss spectroscopy. Nano Lett 2014; 14:3799-808. [PMID: 24955651 DOI: 10.1021/nl5009053] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We present a scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS) investigation of gold nanosphere chains with lengths varying from 1 to 5 particles. We show localized EELS signals from the chains and identify energy-loss peaks arising due to l = 1, 2, 3, 4, and 5 plasmon modes through the use of EELS mapping. We also show the evolution of the energy of these modes as the length of a given chain increases, and we find that a chain containing N particles can accommodate at least N experimentally observable modes, in addition to the transverse mode. As the chain length is increased by the addition of one more gold particle to the chain, the new N + 1 mode becomes the highest energy mode, while the existing modes lower their energy and eventually asymptote as they delocalize along the chain. We also show that modes become increasingly difficult to detect with the EELS technique as l approaches N. The data are compared to numerical simulations.
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Affiliation(s)
- Steven J Barrow
- School of Chemistry and Bio21 Institute, University of Melbourne , Parkville, Victoria 3010, Australia
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29
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Abstract
Fabrication of one-dimensional arrays of crystalline nanoparticles with tunable particle size and spacing (down to 20 nm) is demonstrated. The individual nanocrystals are pentagonal prisms, and the arrays are up to 11 μm in length, with some arrays containing >50 nanocrystals. Precise particle morphology and interparticle spacing can be maintained down the array. The far-field scattering spectra of the arrays show the near-fields of the nanocrystals are coupled. The method is fast and produces precise, well-defined, coupled plasmonic arrays with optical properties that match well to theory.
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Affiliation(s)
- Alison M Funston
- †School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | - Daniel E Gómez
- ‡CSIRO, Materials Science and Engineering, Private Bag 33, Clayton, Victoria, 3168, Australia
- §Melbourne Centre for Nanofabrication, Clayton VIC 3168, Australia
| | - Matthias Karg
- ∥School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Kristy C Vernon
- ⊥Applied Optics and Nanotechnology Group, Queensland University of Technology, 2 George Street, Brisbane, QLD, 4001, Australia
| | - Timothy J Davis
- ‡CSIRO, Materials Science and Engineering, Private Bag 33, Clayton, Victoria, 3168, Australia
- §Melbourne Centre for Nanofabrication, Clayton VIC 3168, Australia
| | - Paul Mulvaney
- ∥School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, Victoria, 3010, Australia
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30
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Anstaett P, Zheng Y, Thai T, Funston AM, Bach U, Gasser G. Synthesis of stable peptide nucleic acid-modified gold nanoparticles and their assembly onto gold surfaces. Angew Chem Int Ed Engl 2013; 52:4217-20. [PMID: 23460137 DOI: 10.1002/anie.201209684] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/30/2013] [Indexed: 11/10/2022]
Affiliation(s)
- Philipp Anstaett
- Institute of Inorganic Chemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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31
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Anstaett P, Zheng Y, Thai T, Funston AM, Bach U, Gasser G. Synthesis of Stable Peptide Nucleic Acid-Modified Gold Nanoparticles and their Assembly onto Gold Surfaces. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201209684] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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32
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Kumar J, Wei X, Barrow S, Funston AM, Thomas KG, Mulvaney P. Surface plasmon coupling in end-to-end linked gold nanorod dimers and trimers. Phys Chem Chem Phys 2013; 15:4258-64. [DOI: 10.1039/c3cp44657c] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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33
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Wishart JF, Funston AM, Szreder T, Cook AR, Gohdo M. Electron solvation dynamics and reactivity in ionic liquids observed by picosecond radiolysis techniques. Faraday Discuss 2012; 154:353-63; discussion 439-64, 465-71. [DOI: 10.1039/c1fd00065a] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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34
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Barrow SJ, Funston AM, Gómez DE, Davis TJ, Mulvaney P. Surface plasmon resonances in strongly coupled gold nanosphere chains from monomer to hexamer. Nano Lett 2011; 11:4180-7. [PMID: 21879717 DOI: 10.1021/nl202080a] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We present experimental data on the light scattering properties of linear chains of gold nanoparticles with up to six nanoparticles and an interparticle spacing of 1 nm. A red shift of the surface plasmon resonance with increasing chain length is observed. An exponential model applied to the experimental data allows determination of an asymptotic maximum resonance at a chain length of 10-12 particles. The optical data are compared with analytical and numerical calculation methods (EEM and BEM).
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Affiliation(s)
- Steven J Barrow
- School of Chemistry and Bio21 Institute, The University of Melbourne , Parkville, Victoria, 3010, Australia
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35
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Abstract
An experimental and theoretical examination of the coupling modes within superstructures of gold nanorod trimers is presented. The experimentally determined spectrum of the nanorod trimers is reported and the modes are elucidated using an electrostatic eigenmode method based on the coupling of evanescent electric fields. The theory is able to reproduce the experimental spectrum well, and the nature of the modes and interactions are discussed.
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Affiliation(s)
- Alison M Funston
- School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, Victoria, VIC 3010, Australia.
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36
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Katz-Boon H, Rossouw CJ, Weyland M, Funston AM, Mulvaney P, Etheridge J. Three-dimensional morphology and crystallography of gold nanorods. Nano Lett 2011; 11:273-278. [PMID: 21182286 DOI: 10.1021/nl103726k] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We determine the three-dimensional shape, to within 1 nm resolution, of single-crystal gold nanorods grown in the presence of silver ions using electron tomography and thickness profile measurements. We find that, contrary to the current literature, the octagonal side-facets are sparsely packed atomic planes all belonging to the same symmetry-equivalent family, {0 5 12}. Furthermore, the rod ends terminate in a pyramid with slightly different facets, and each pyramid is connected to the sides by four small {0 5 12} "bridging" facets.
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Affiliation(s)
- Hadas Katz-Boon
- Department of Materials Engineering and Monash Centre for Electron Microscopy, Monash University, Victoria 3800, Australia
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37
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Vernon KC, Funston AM, Novo C, Gómez DE, Mulvaney P, Davis TJ. Influence of particle-substrate interaction on localized plasmon resonances. Nano Lett 2010; 10:2080-6. [PMID: 20476750 DOI: 10.1021/nl100423z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We present a theory for determining the localized surface plasmon resonance shifts of arbitrarily shaped metal nanoparticles on a substrate. Using a pseudoparticle concept, an expression for the particle-substrate interaction is derived, providing both physical insight and formulas to estimate the shifted plasmon resonance. The theory is verified against measured scattering spectra of nanorods on substrates. Simple formulas are provided to calculate the resonance of nanorods, spheres, and ellipsoids on dielectric substrate.
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Affiliation(s)
- Kristy C Vernon
- CSIRO, Materials Science and Engineering and Future Manufacturing Flagship, Private Bag 33, Clayton, VIC 3168, Australia.
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38
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Abstract
This perspective reviews recent developments in the synthesis, electrochemistry, and optical properties of gold nanoparticles, with emphasis on papers initiating the developments and with an eye to their consequences. Key aspects of Au nanoparticle synthesis have included the two-phase synthesis of thiolated nanoparticles, the sequestration and reduction of Au salts within dendrimers, the controlled growth of larger particles of well-defined shapes via the seeded approach, and the assembling of a variety of nanoparticle networks and nanostructures. The electrochemistry of thiolated Au nanoparticles is systemized as regions of bulk-continuum voltammetry, voltammetry reflective of quantized double-layer charging, and molecule-like voltammetry reflective of molecular energy gaps. These features are principally determined by the nanoparticle core. Interesting multielectron Au nanoparticle voltammetry is observed when the thiolate ligand shell has been decorated with redox groupings. Another development is that Au nanoparticles were discovered to exhibit unanticipated properties as heterogeneous catalysts, starting with the low-temperature oxidation of CO. Substantial progress has also been made in understanding the surface plasmon spectroscopy of Au nanoparticles and nanorods. The need to investigate the optical properties of metal particles of a single, well-defined shape and size has motivated the development of a number of new techniques, leading to the study of electron transfer and redox catalysis on single nanoparticles.
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Affiliation(s)
- Rajesh Sardar
- Kenan Laboratories of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, USA
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39
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Affiliation(s)
- Carolina Novo
- School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Alison M. Funston
- School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Ann K. Gooding
- School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Paul Mulvaney
- School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, VIC, 3010, Australia
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Rodríguez-Fernández J, Funston AM, Pérez-Juste J, Alvarez-Puebla RA, Liz-Marzán LM, Mulvaney P. The effect of surface roughness on the plasmonic response of individual sub-micron gold spheres. Phys Chem Chem Phys 2009; 11:5909-14. [PMID: 19588012 DOI: 10.1039/b905200n] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nanoscale surface corrugation strongly determines the plasmonic response of gold nanoparticles with dimensions of several tens of nanometres. Scattering spectra of individual spheres with a rough surface were found to red-shift and broaden. The plasmon modes exhibited quadrupole damping, in contrast to particles with smooth surfaces. Additionally, rougher spheres display a higher SERS activity, which demonstrates the crucial role of nanoscale surface texturing on the plasmonic response of gold particles.
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Funston AM, Novo C, Davis TJ, Mulvaney P. Plasmon coupling of gold nanorods at short distances and in different geometries. Nano Lett 2009; 9:1651-8. [PMID: 19271775 DOI: 10.1021/nl900034v] [Citation(s) in RCA: 355] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The experimentally determined scattering spectra of discrete, crystalline, gold nanorod dimers arranged side-to-side, end-to-end, at right angles in different orientations and also with longitudinal offsets are reported along with the electron micrographs of the individual dimers. The spectra exhibit both red- and blue-shifted surface plasmon resonances, consistent with the plasmon hybridization model. However, the plasmon coupling constant for gold dimers with less than a few nanometers separation between the particles does not obey the exponential dependence predicted by the Universal Plasmon Ruler equation. The experimentally determined spectra are compared with electrodynamic calculations and the interactions between the individual rod plasmons in different dimer orientations are elucidated.
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Affiliation(s)
- Alison M Funston
- School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, Victoria, Australia.
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Novo C, Funston AM, Mulvaney P. Direct observation of chemical reactions on single gold nanocrystals using surface plasmon spectroscopy. Nat Nanotechnol 2008; 3:598-602. [PMID: 18838998 DOI: 10.1038/nnano.2008.246] [Citation(s) in RCA: 275] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Accepted: 07/30/2008] [Indexed: 05/25/2023]
Abstract
Heterogeneous catalysts have been pivotal to the development of the modern chemical industry and are essential for catalysing many industrial reactions. However, reaction rates are different for every individual catalyst particle and depend upon each particle's morphology and size, crystal structure and composition. Measuring the rates of reaction on single nanocrystals will enable the role of catalyst structure to be quantified. Here, using surface plasmon spectroscopy, we have directly observed the kinetics of atomic deposition onto a single gold nanocrystal and also monitored electron injection and extraction during a redox reaction involving the oxidation of ascorbic acid on a gold nanocrystal surface. These results constitute the first direct measurement of the rates of redox catalysis on single nanocrystals.
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Affiliation(s)
- Carolina Novo
- School of Chemistry & Bio21 Institute, University of Melbourne, Parkville, Vic. 3010, Australia
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Myroshnychenko V, Rodríguez-Fernández J, Pastoriza-Santos I, Funston AM, Novo C, Mulvaney P, Liz-Marzán LM, García de Abajo FJ. Modelling the optical response of gold nanoparticles. Chem Soc Rev 2008; 37:1792-805. [DOI: 10.1039/b711486a] [Citation(s) in RCA: 934] [Impact Index Per Article: 58.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
The ion radicals of two series of platinum acetylide oligomers have been subjected to study by electrochemical and pulse radiolysis/transient absorption methods. One series of oligomers, Ptn, has the general structure Ph-C[triple bond]C-[Pt(PBu3)2-C[triple bond]C-(1,4-Ph)-C[triple bond]C-]n-Pt(PBu3)2-C[triple bond]C-Ph (where x=0-4, Ph=phenyl and 1,4-Ph=1,4-phenylene). The second series of oligomers, Pt4Tn, contain a thiophene oligomer core, -C[triple bond]C-(2,5-Th)n-C[triple bond]C- (where n=1-3 and 2,5-Th=2,5-thienylene), capped on both ends with -Pt(PBu3)2-C[triple bond]C-(1,4-Ph)-C[triple bond]C-Pt(PBu3)2-C[triple bond]C-Ph segments. Electrochemical studies reveal that all of the oligomers feature reversible or quasi-reversible one-electron oxidation at potentials less than 1 V versus SCE. These oxidations are assigned to the formation of radical cations on the platinum acetylide chains. For the longer oligomers multiple, reversible one-electron waves are observed at potentials less than 1 V, indicating that multiple positive polarons can be produced on the oligomers. Pulse-radiolysis/transient absorption spectroscopy has been used to study the spectra and dynamics of the cation and anion radical states of the oligomers in dichloroethane and tetrahydrofuran solutions, respectively. All of the ion radicals exhibit two allowed absorption bands: one in the visible region and the second in the near-infrared region. The ion radical spectra shift with oligomer length, suggesting that the polarons are delocalized to some extent on the platinum acetylide chains. Analysis of the electrochemical and pulse radiolysis data combined with the density functional theory calculations on model ion radicals provides insight into the electronic structure of the positive and negative ion radical states of the oligomers. A key conclusion of the work is that the polaron states are concentrated on relatively short oligomer segments.
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Affiliation(s)
- Thomas Cardolaccia
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611, USA
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Funston AM, Lymar SV, Saunders-Price B, Czapski G, Miller JR. Rate and Driving Force for Protonation of Aryl Radical Anions in Ethanol. J Phys Chem B 2007; 111:6895-902. [PMID: 17523623 DOI: 10.1021/jp071450h] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Aryl radical anions created in liquid alcohols decay on the microsecond time scale by transfer of protons from the solvent. This paper reports a 4.5 decade range of rate constants for proton transfer from a single weak acid, ethanol, to a series of unsubstituted aryl radical anions, Ar-*. The rate constants correlate with free energy change, DeltaG(o), despite wide variations in the two factors that contribute to DeltaG(o): (a) the reduction potentials of the aryls and (b) the Ar-H* bond strengths in the product radicals. For aryl radical anions containing CH2OH substituents, such as 2,2'-biphenyldimethanol*- which is protonated with a rate constant of 3x10(9) s(-1), the faster rates do not fit well in the free energy correlation, suggesting a change in mechanism.
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Affiliation(s)
- Alison M Funston
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, USA
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Novo C, Funston AM, Pastoriza-Santos I, Liz-Marzán LM, Mulvaney P. Spectroscopy and High-Resolution Microscopy of Single Nanocrystals by a Focused Ion Beam Registration Method. Angew Chem Int Ed Engl 2007; 46:3517-20. [PMID: 17394272 DOI: 10.1002/anie.200700033] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Carolina Novo
- School of Chemistry, The University of Melbourne, Victoria, 3010, Australia
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Funston AM, Fadeeva TA, Wishart JF, Castner EW. Fluorescence Probing of Temperature-Dependent Dynamics and Friction in Ionic Liquid Local Environments. J Phys Chem B 2007; 111:4963-77. [PMID: 17439268 DOI: 10.1021/jp068298o] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The solvation dynamics and local orientational friction for a series of four ionic liquids have been probed using coumarin 153 (C153) as a function of temperature. These ionic liquids are comprised of nonaromatic organic cations paired with a common anion, bis(trifluoromethylsulfonyl)imide (NTf(2)-). The specific liquids are as follows: N-methyl-tri-N-butylammonium NTf(2)- (N(1444)+/NTf(2)-), N-hexyl-tri-N-butylammonium NTf(2)- (N(6444)+/NTf(2)-), N-methyl-N-butylpyrrolidinium NTf(2)- (Pyrr(14)+/NTf(2)-), and N-methyl-N-ethoxyethylpyrrolidinium NTf(2)- (Pyrr(1(2O2))+/NTf(2)-). The observed solvation dynamics and fluorescence depolarization dynamics occur over a broad range of time scales that can only be adequately fit by functions including three or more exponential components. Stretched exponential distributions cannot adequately fit our data. The solvation and reorientational dynamics of the C153 probe are studied over a range of temperatures from 278.2 to 353.2 K. For both the solvation dynamics and the probe reorientational dynamics, the observed temperature dependence is well fit by a Vogel-Tammann-Fulcher law. To correlate the observed microscopic dynamics with macroscopic physical properties, temperature-dependent viscosities are also measured. Differential scanning calorimetry is used to study the thermodynamics of the phase transitions from the liquid to supercooled liquid to glassy states. For the two tetraalkylammonium liquids, the observed melting transitions occur near 300 K, so we are able to study the dynamics in a clearly supercooled regime. Very long time scale orientational relaxation time constants dynamics on the order of 100 ns are observed in the C153 fluorescence anisotropy. These are interpreted to arise from long-lived local structures in the environment surrounding the C153 probe.
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Affiliation(s)
- Alison M Funston
- School of Chemistry, University of Melbourne, Melbourne, Australia
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Funston AM, Silverman EE, Schanze KS, Miller JR. Spectroscopy and Transport of the Triplet Exciton in a Terthiophene End-Capped Poly(phenylene ethynylene). J Phys Chem B 2006; 110:17736-42. [PMID: 16956256 DOI: 10.1021/jp061114l] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Triplet states of poly(phenylene ethynylene), (3)PPE(*), not easily formed by direct photoexcitation, were produced by pulse radiolysis in toluene, along with triplet states of T(3)PPE having terthiophene end-caps. Intense triplet-triplet absorption maxima, epsilon(680)((3)PPE(*)) = 9.5 x 10(4) M(-1) cm(-1) and epsilon(780)((3)T(3)PPE(*)) = 2.8 x 10(4) M(-1) cm(-1) enable identification of these two species, which have triplet energies of 2.12 and 1.77 eV determined in bimolecular energy transfer equilibria. Bleaching of ground-state absorption measures (3)PPE(*) to be the delocalized over a 1.8-nm length. Triplet states formed in the PPE chains were transported to and trapped by the end caps in a time <<5 ns.
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Affiliation(s)
- Alison M Funston
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA
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Abstract
We have investigated the ultrafast molecular dynamics of five pyrrolidinium cation room temperature ionic liquids using femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy. The ionic liquids studied are N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P14+/NTf2-), N-methoxyethyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P1EOE+/NTf2-), N-ethoxyethyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P1EOE+/NTf2-), N-ethoxyethyl-N-methylpyrrolidinium bromide P1EOE+, and N-ethoxyethyl-N-methylpyrrolidinium dicyanoamide P1EOE+/DCA-). For comparing dynamics among the five ionic liquids, we categorize the ionic liquids into two groups. One group of liquids comprises the three pyrrolidinium cations P14+, P1EOM+, and P1EOE+ paired with the NTf2- anion. The other group of liquids consists of the P1EOE+ cation paired with each of the three anions NTf2-, Br-, and DCA-. The overdamped relaxation for time scales longer than 2 ps has been fit by a triexponential function for each of the five pyrrolidinium ionic liquids. The fast ( approximately 2 ps) and intermediate (approximately 20 ps) relaxation time constants vary little among these five ionic liquids. However, the slow relaxation time constant correlates with the viscosity. Thus, the Kerr spectra in the range from 0 to 750 cm(-1) are quite similar for the group of three pyrrolidinium ionic liquids paired with the NTf2- anion. The intermolecular vibrational line shapes between 0 and 150 cm(-1) are fit to a multimode Brownian oscillator model; adequate fits required at least three modes to be included in the line shape.
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Affiliation(s)
- Hideaki Shirota
- Department of Chemistry & Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8087, USA
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