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Del Mar García Martín C, Ramírez O, Bonardd S, López-Darias M, Franco L, M'Rabet Y, Khwaldia K, Díaz Díaz D. Unlocking the potential of Opuntia species mucilage in chemistry. Int J Biol Macromol 2024; 268:131647. [PMID: 38653432 DOI: 10.1016/j.ijbiomac.2024.131647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 04/11/2024] [Accepted: 04/14/2024] [Indexed: 04/25/2024]
Abstract
Herein, we describe a detailed protocol to extract the mucilage from different species of the genus Opuntia spp. (i.e., Opuntia Ficus (OFi), Opuntia Dillenii (ODi) and Opuntia Robusta (ORo)). The extracted mucilage was characterized by NMR, FTIR-ATR, HPLC, and TGA. OFi was found to have the highest phenolic content, 7.84 ± 1.93 mg catechol/g mucilage. The mucilage from the three species were characterized by having a high content of monosaccharides, being mannose and glucose the most abundant components (ca. 48-73 % and 23-35 %, respectively). In the context of biomass revalorization, the mucilage was proven to serve as a reducing and stabilizing agent in the synthesis of gold nanoparticles (AuNP/mucilage). The synthesis was optimized with a mucilage concentration of 2 mg/mL using 12.5 μL of KAuCl4 and was carried out at 80 °C for 90 min. This protocol afforded spherical nanoparticles with an average size of 9.7 ± 4.0 nm that were stable for at least 14 days, as demonstrated by TEM. Synthesized AuNP/mucilage was evaluated as a plasmonic catalyst for the reduction of 4-nitrophenol as model reaction, showing a considerable enhancement in its kapp of 97 % under white light and a decrease of 24.8 % in its activation energy.
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Affiliation(s)
- Cristina Del Mar García Martín
- Departamento de Química Orgánica Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez 3, La Laguna 38206, Tenerife, Spain; Instituto Universitario de Bio-Orgánica Antonio González, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Tenerife, Spain
| | - Oscar Ramírez
- Departamento de Química Orgánica Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez 3, La Laguna 38206, Tenerife, Spain; Instituto Universitario de Bio-Orgánica Antonio González, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Tenerife, Spain; Departamento de Química Física, Facultad de Química y de Farmacia, Pontificia Universidad Católica de Chile, Casilla 302, Correo 22, Santiago, Chile
| | - Sebastian Bonardd
- Centro de Física de Materiales (CSIC, UPV/EHU)-Materials Physics Center (MPC), 20018 Donostia-San Sebastián, Spain; Department of Polymers and Advanced Materials: Physics, Chemistry and Technology, University of the Basque Country UPV/EHU, 20018 Donostia-San Sebastián, Spain
| | - Marta López-Darias
- IPNA-CSIC, Avda. Astrofísico Fco. Sánchez 3, 38206 San Cristóbal de La Laguna, Tenerife, Spain
| | - Lourdes Franco
- Departament d'Enginyeria Quimica, Universitat Politecnica de Catalunya, Escola d'Enginyeria de Barcelona Est-EEBE, 08019 Barcelona, Spain; Barcelona Research Center for Multiscale Science and Engineering, Universitat Politecnica de Catalunya, Escola d'Enginyeria de Barcelona Est-EEBE, 08019 Barcelona, Spain
| | - Yassine M'Rabet
- Laboratoire des Substances Naturelles, Institut National de Recherche et d'Analyse Physico-chimique (INRAP), Biotech Pole, Sidi Thabet 2020, Tunisia
| | - Khaoula Khwaldia
- Laboratoire des Substances Naturelles, Institut National de Recherche et d'Analyse Physico-chimique (INRAP), Biotech Pole, Sidi Thabet 2020, Tunisia
| | - David Díaz Díaz
- Departamento de Química Orgánica Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez 3, La Laguna 38206, Tenerife, Spain; Instituto Universitario de Bio-Orgánica Antonio González, Universidad de La Laguna, Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Tenerife, Spain.
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2
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Calvo R, Pini V, Thon A, Saad A, Salvador-Matar A, Manso Silván M, Ahumada Ó. Amplitude-Resolved Single Particle Spectrophotometry: A Robust Tool for High-Throughput Size Characterization of Plasmonic Nanoparticles. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2401. [PMID: 37686909 PMCID: PMC10490240 DOI: 10.3390/nano13172401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/16/2023] [Accepted: 08/21/2023] [Indexed: 09/10/2023]
Abstract
Plasmonic nanoparticles have a wide range of applications in science and industry. Despite the numerous synthesis methods reported in the literature over the last decades, achieving precise control over the size and shape of large nanoparticle populations remains a challenge. Since variations in size and shape significantly affect the plasmonic properties of nanoparticles, accurate metrological techniques to characterize their morphological features are essential. Here, we present a novel spectrophotometric method, called Amplitude-Resolved Single Particle Spectrophotometry, that can measure the individual sizes of thousands of particles with nanometric accuracy in just a few minutes. This new method, based on the measurement of the scattering amplitude of each nanoparticle, overcomes some of the limitations observed in previous works and theoretically allows the characterization of nanoparticles of any size with a simple extra calibration step. As proof of concept, we characterized thousands of spherical nanoparticles of different sizes. This new method shows excellent accuracy, with less than a 3% discrepancy in direct comparison with transmission electron microscopy. Although the effectiveness of this method has been demonstrated with spherical nanoparticles, its real strength lies in its adaptability to more complex geometries by using an alternative analytical method to the one described here.
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Affiliation(s)
- Rodrigo Calvo
- Mecwins S.A., Ronda de Poniente, 15 2°D, Tres Cantos, 28760 Madrid, Spain
- Departamento de Física Aplicada, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain
| | - Valerio Pini
- Mecwins S.A., Ronda de Poniente, 15 2°D, Tres Cantos, 28760 Madrid, Spain
| | - Andreas Thon
- Mecwins S.A., Ronda de Poniente, 15 2°D, Tres Cantos, 28760 Madrid, Spain
| | - Asis Saad
- Mecwins S.A., Ronda de Poniente, 15 2°D, Tres Cantos, 28760 Madrid, Spain
| | | | - Miguel Manso Silván
- Departamento de Física Aplicada, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain
- Centro de Microanálisis de Materiales, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain
| | - Óscar Ahumada
- Mecwins S.A., Ronda de Poniente, 15 2°D, Tres Cantos, 28760 Madrid, Spain
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3
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Rayan B, Barnea E, Khokhlov A, Upcher A, Landau M. Differential fibril morphologies and thermostability determine functional roles of Staphylococcus aureus PSMα1 and PSMα3. Front Mol Biosci 2023; 10:1184785. [PMID: 37469708 PMCID: PMC10353841 DOI: 10.3389/fmolb.2023.1184785] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Accepted: 06/21/2023] [Indexed: 07/21/2023] Open
Abstract
Phenol-soluble modulins (PSMs) are virulent peptides secreted by staphylococci that undergo self-assembly into amyloid fibrils. This study focuses on Staphylococcus aureus PSMα1 and PSMα3, which share homologous sequences but exhibit distinct amyloid fibril structures. Upon subjecting PSMα1 to an 80°C heat shock, it fibrillates into cross-β structures, resulting in the loss of cytotoxic activity. Conversely, PSMα3 cross-α fibrils undergo reversible disaggregation upon heat shock, leading to the recovery of cytotoxicity. The differential thermostability probably arises from the presence of hydrogen bonds along the β-strands within the β-sheets of the cross-β fibrils. We propose that the breakdown of PSMα3 fibrils into soluble species, potentially co-aggregating with membrane lipids, is crucial for its toxic process and enables the reversible modulation of its biological activity under stress conditions. In contrast, the formation of robust and irreversible cross-β fibrils by PSMα1 corresponds to its role in biofilm stability. These findings emphasize how the unique fibril morphologies and thermostability of PSMα1 and PSMα3 shape their functional roles in various environments of S. aureus.
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Affiliation(s)
- Bader Rayan
- Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Eilon Barnea
- Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Alexander Khokhlov
- Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Alexander Upcher
- Ilse Katz Institute for Nanoscale Science and Technology, Ben Gurion University of the Negev, Beer-Sheva, Israel
| | - Meytal Landau
- Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
- Centre for Structural Systems Biology (CSSB), Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
- The Center for Experimental Medicine, Universitätsklinikum Hamburg-Eppendorf (UKE), Hamburg, Germany
- European Molecular Biology Laboratory (EMBL), Hamburg, Germany
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Mistewicz K, Das TK, Nowacki B, Smalcerz A, Kim HJ, Hajra S, Godzierz M, Masiuchok O. Bismuth sulfoiodide (BiSI) nanorods: synthesis, characterization, and photodetector application. Sci Rep 2023; 13:8800. [PMID: 37258802 DOI: 10.1038/s41598-023-35899-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Accepted: 05/25/2023] [Indexed: 06/02/2023] Open
Abstract
The nanorods of bismuth sulfoiodide (BiSI) were synthesized at relatively low temperature (393 K) through a wet chemical method. The crystalline one-dimensional (1D) structure of the BiSI nanorods was confirmed using high resolution transmission microscopy (HRTEM). The morphology and chemical composition of the material were examined by applying scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively. The average diameter of 126(3) nm and length of 1.9(1) µm of the BiSI nanorods were determined. X-ray diffraction (XRD) revealed that prepared material consists of a major orthorhombic BiSI phase (87%) and a minor amount of hexagonal Bi13S18I2 phase (13%) with no presence of other residual phases. The direct energy band gap of 1.67(1) eV was determined for BiSI film using diffuse reflectance spectroscopy (DRS). Two types of photodetectors were constructed from BiSI nanorods. The first one was traditional photoconductive device based on BiSI film on stiff glass substrate equipped with Au electrodes. An influence of light intensity on photocurrent response to monochromatic light (λ = 488 nm) illumination was studied at a constant bias voltage. The novel flexible photo-chargeable device was the second type of prepared photodetectors. It consisted of BiSI film and gel electrolyte layer sandwiched between polyethylene terephthalate (PET) substrates coated with indium tin oxide (ITO) electrodes. The flexible self-powered BiSI photodetector exhibited open-circuit photovoltage of 68 mV and short-circuit photocurrent density of 0.11 nA/cm2 under light illumination with intensity of 0.127 W/cm2. These results confirmed high potential of BiSI nanorods for use in self-powered photodetectors and photo-chargeable capacitors.
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Affiliation(s)
- Krystian Mistewicz
- Institute of Physics - Center for Science and Education, Silesian University of Technology, Krasińskiego 8, 40-019, Katowice, Poland.
| | - Tushar Kanti Das
- Institute of Physics - Center for Science and Education, Silesian University of Technology, Krasińskiego 8, 40-019, Katowice, Poland
| | - Bartłomiej Nowacki
- Department of Industrial Informatics, Faculty of Materials Science, Joint Doctorate School, Silesian University of Technology, Krasinskiego 8, 40-019, Katowice, Poland
| | - Albert Smalcerz
- Department of Industrial Informatics, Faculty of Materials Science, Silesian University of Technology, Krasinskiego 8, 40-019, Katowice, Poland
| | - Hoe Joon Kim
- Department of Robotics and Mechatronics Engineering, Daegu Gyeongbuk Institute of Science and Technology, Daegu, 42988, Republic of Korea
| | - Sugato Hajra
- Department of Robotics and Mechatronics Engineering, Daegu Gyeongbuk Institute of Science and Technology, Daegu, 42988, Republic of Korea
| | - Marcin Godzierz
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819, Zabrze, Poland
- International Polish-Ukrainian Research Laboratory Formation and Characterization of Advanced Polymers and Polymer Composites (ADPOLCOM), Kyiv, Ukraine
| | - Olha Masiuchok
- Centre of Polymer and Carbon Materials, Polish Academy of Sciences, M. Curie-Skłodowskiej 34, 41-819, Zabrze, Poland
- International Polish-Ukrainian Research Laboratory Formation and Characterization of Advanced Polymers and Polymer Composites (ADPOLCOM), Kyiv, Ukraine
- E.O. Paton Electric Welding Institute, National Academy of Sciences of Ukraine, 11 Kazymyr Malevych Str, Kyiv, 03680, Ukraine
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Volders J, Elen K, Raes A, Ninakanti R, Kelchtermans AS, Sastre F, Hardy A, Cool P, Verbruggen SW, Buskens P, Van Bael MK. Sunlight-Powered Reverse Water Gas Shift Reaction Catalysed by Plasmonic Au/TiO 2 Nanocatalysts: Effects of Au Particle Size on the Activity and Selectivity. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:4153. [PMID: 36500776 PMCID: PMC9738324 DOI: 10.3390/nano12234153] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 11/14/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
This study reports the low temperature and low pressure conversion (up to 160 °C, p = 3.5 bar) of CO2 and H2 to CO using plasmonic Au/TiO2 nanocatalysts and mildly concentrated artificial sunlight as the sole energy source (up to 13.9 kW·m-2 = 13.9 suns). To distinguish between photothermal and non-thermal contributors, we investigated the impact of the Au nanoparticle size and light intensity on the activity and selectivity of the catalyst. A comparative study between P25 TiO2-supported Au nanocatalysts of a size of 6 nm and 16 nm displayed a 15 times higher activity for the smaller particles, which can only partially be attributed to the higher Au surface area. Other factors that may play a role are e.g., the electronic contact between Au and TiO2 and the ratio between plasmonic absorption and scattering. Both catalysts displayed ≥84% selectivity for CO (side product is CH4). Furthermore, we demonstrated that the catalytic activity of Au/TiO2 increases exponentially with increasing light intensity, which indicated the presence of a photothermal contributor. In dark, however, both Au/TiO2 catalysts solely produced CH4 at the same catalyst bed temperature (160 °C). We propose that the difference in selectivity is caused by the promotion of CO desorption through charge transfer of plasmon generated charges (as a non-thermal contributor).
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Affiliation(s)
- Jordi Volders
- Design and Synthesis of Inorganic Materials (DESINe), Institute for Materials Research, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium
- Imec Vzw, Imomec Associated Laboratory, Wetenschapspark 1, 3590 Diepenbeek, Belgium
- EnergyVille, Thor Park 8320, 3600 Genk, Belgium
| | - Ken Elen
- Design and Synthesis of Inorganic Materials (DESINe), Institute for Materials Research, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium
- Imec Vzw, Imomec Associated Laboratory, Wetenschapspark 1, 3590 Diepenbeek, Belgium
- EnergyVille, Thor Park 8320, 3600 Genk, Belgium
| | - Arno Raes
- Sustainable Energy, Air & Water Technology (DuEL), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - Rajeshreddy Ninakanti
- Sustainable Energy, Air & Water Technology (DuEL), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - An-Sofie Kelchtermans
- Design and Synthesis of Inorganic Materials (DESINe), Institute for Materials Research, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium
- Imec Vzw, Imomec Associated Laboratory, Wetenschapspark 1, 3590 Diepenbeek, Belgium
- EnergyVille, Thor Park 8320, 3600 Genk, Belgium
| | - Francesc Sastre
- The Netherlands Organisation for Applied Scientific Research (TNO), High Tech Campus 25, 5656 AE Eindhoven, The Netherlands
| | - An Hardy
- Design and Synthesis of Inorganic Materials (DESINe), Institute for Materials Research, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium
- Imec Vzw, Imomec Associated Laboratory, Wetenschapspark 1, 3590 Diepenbeek, Belgium
- EnergyVille, Thor Park 8320, 3600 Genk, Belgium
| | - Pegie Cool
- Laboratory of Adsorption and Catalysis, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Sammy W. Verbruggen
- Sustainable Energy, Air & Water Technology (DuEL), University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - Pascal Buskens
- Design and Synthesis of Inorganic Materials (DESINe), Institute for Materials Research, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium
- The Netherlands Organisation for Applied Scientific Research (TNO), High Tech Campus 25, 5656 AE Eindhoven, The Netherlands
| | - Marlies K. Van Bael
- Design and Synthesis of Inorganic Materials (DESINe), Institute for Materials Research, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium
- Imec Vzw, Imomec Associated Laboratory, Wetenschapspark 1, 3590 Diepenbeek, Belgium
- EnergyVille, Thor Park 8320, 3600 Genk, Belgium
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Bryche JF, Vega M, Tempez A, Brulé T, Carlier T, Moreau J, Chaigneau M, Charette PG, Canva M. Spatially-Localized Functionalization on Nanostructured Surfaces for Enhanced Plasmonic Sensing Efficacy. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3586. [PMID: 36296775 PMCID: PMC9609756 DOI: 10.3390/nano12203586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/07/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
This work demonstrates the enhancement in plasmonic sensing efficacy resulting from spatially-localized functionalization on nanostructured surfaces, whereby probe molecules are concentrated in areas of high field concentration. Comparison between SERS measurements on nanostructured surfaces (arrays of nanodisks 110 and 220 nm in diameter) with homogeneous and spatially-localized functionalization with thiophenol demonstrates that the Raman signal originates mainly from areas with high field concentration. TERS measurements with 10 nm spatial resolution confirm the field distribution profiles predicted by the numerical modeling. Though this enhancement in plasmonic sensing efficacy is demonstrated with SERS, results apply equally well to any type of optical/plasmonic sensing on functionalized surfaces with nanostructuring.
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Affiliation(s)
- Jean-François Bryche
- Laboratoire Nanotechnologies Nanosystèmes (LN2-IRL 3463)-CNRS, Université de Sherbrooke, 3000 Boulevard de l’Université, Sherbrooke, QC J1K OA5, Canada
- Institut Interdisciplinaire d’Innovation Technologique (3IT), 3000 Boulevard de l’Université, Sherbrooke, QC J1K OA5, Canada
| | - Marlo Vega
- Laboratoire Nanotechnologies Nanosystèmes (LN2-IRL 3463)-CNRS, Université de Sherbrooke, 3000 Boulevard de l’Université, Sherbrooke, QC J1K OA5, Canada
- Institut Interdisciplinaire d’Innovation Technologique (3IT), 3000 Boulevard de l’Université, Sherbrooke, QC J1K OA5, Canada
- Laboratoire Charles Fabry—Institut d’Optique Graduate School, Université Paris-Saclay, CNRS, 91120 Palaiseau, France
| | | | | | | | - Julien Moreau
- Laboratoire Charles Fabry—Institut d’Optique Graduate School, Université Paris-Saclay, CNRS, 91120 Palaiseau, France
| | | | - Paul G. Charette
- Laboratoire Nanotechnologies Nanosystèmes (LN2-IRL 3463)-CNRS, Université de Sherbrooke, 3000 Boulevard de l’Université, Sherbrooke, QC J1K OA5, Canada
- Institut Interdisciplinaire d’Innovation Technologique (3IT), 3000 Boulevard de l’Université, Sherbrooke, QC J1K OA5, Canada
| | - Michael Canva
- Laboratoire Nanotechnologies Nanosystèmes (LN2-IRL 3463)-CNRS, Université de Sherbrooke, 3000 Boulevard de l’Université, Sherbrooke, QC J1K OA5, Canada
- Institut Interdisciplinaire d’Innovation Technologique (3IT), 3000 Boulevard de l’Université, Sherbrooke, QC J1K OA5, Canada
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Plasmon resonance of gold and silver nanoparticle arrays in the Kretschmann (attenuated total reflectance) vs. direct incidence configuration. Sci Rep 2022; 12:15738. [PMID: 36130995 PMCID: PMC9492765 DOI: 10.1038/s41598-022-20117-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 09/08/2022] [Indexed: 11/16/2022] Open
Abstract
While the behaviour of plasmonic solid thin films in the Kretschmann (also known as Attenuated Total Reflection, ATR) configuration is well-understood, the use of discrete nanoparticle arrays in this optical configuration is not thoroughly explored. It is important to do so, since close packed plasmonic nanoparticle arrays exhibit exceptionally strong light-matter interactions by plasmonic coupling. The present work elucidates the optical properties of plasmonic Au and Ag nanoparticle arrays in both the direct normal incidence and Kretschmann configuration by numerical models, that are validated experimentally. First, hexagonal close packed Au and Ag nanoparticle films/arrays are obtained by air–liquid interfacial assembly. The numerical models for the rigorous solution of the Maxwell’s equations are validated using experimental optical spectra of these films before systematically investigating various parameters. The individual far-field/near-field optical properties, as well as the plasmon relaxation mechanism of the nanoparticles, vary strongly as the packing density of the array increases. In the Kretschmann configuration, the evanescent fields arising from p- and s-polarized (or TM and TE polarized) incidence have different directional components. The local evanescent field intensity and direction depends on the polarization, angle of incidence and the wavelength of incidence. These factors in the Kretschmann configuration give rise to interesting far-field as well as near-field optical properties. Overall, it is shown that plasmonic nanoparticle arrays in the Kretschmann configuration facilitate strong broadband absorptance without transmission losses, and strong near-field enhancement. The results reported herein elucidate the optical properties of self-assembled nanoparticle films, pinpointing the ideal conditions under which the normal and the Kretschmann configuration can be exploited in multiple light-driven applications.
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