1
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Bartschmid T, Menath J, Roemling L, Vogel N, Atalay F, Farhadi A, Bourret GR. Au Nanoparticles@Si Nanowire Oligomer Arrays for SERS: Dimers Are Best. ACS APPLIED MATERIALS & INTERFACES 2024; 16:41379-41389. [PMID: 39057191 PMCID: PMC11310913 DOI: 10.1021/acsami.4c10004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Revised: 07/17/2024] [Accepted: 07/18/2024] [Indexed: 07/28/2024]
Abstract
We report the synthesis of vertically aligned silicon nanowire (VA-SiNW) oligomer arrays coated with Au nanoparticle (NP) monolayers via a combination of colloidal lithography, metal-assisted chemical etching, and directed NP assembly. Arrays of SiNW monomers (i.e., isolated NWs), dimers, and tetramers are synthesized, decorated with AuNPs, and tested for their performance in surface-enhanced Raman spectroscopy. The ∼20 nm AuNPs easily enter within the ca. 40 nm gaps of the SiNW oligomers, thus reaching the hot spot region. At 785 nm excitation, the AuNPs@SiNW dimer arrays provide the highest Raman signal, in agreement with electromagnetic simulations showing a high electric field enhancement at the Au/Si interface within the dimer gap region.
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Affiliation(s)
- Theresa Bartschmid
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, A-5020 Salzburg, Austria
| | - Johannes Menath
- Institute
of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Lukas Roemling
- Institute
of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Nicolas Vogel
- Institute
of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Furkan Atalay
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, A-5020 Salzburg, Austria
| | - Amin Farhadi
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, A-5020 Salzburg, Austria
| | - Gilles R. Bourret
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, A-5020 Salzburg, Austria
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2
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Tzadka S, Ureña Martin C, Toledo E, Yassin AAK, Pandey A, Le Saux G, Porgador A, Schvartzman M. A Novel Approach for Colloidal Lithography: From Dry Particle Assembly to High-Throughput Nanofabrication. ACS APPLIED MATERIALS & INTERFACES 2024; 16:17846-17856. [PMID: 38549366 DOI: 10.1021/acsami.3c18554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
We introduce a novel approach for colloidal lithography based on the dry particle assembly into a dense monolayer on an elastomer, followed by mechanical transfer to a substrate of any material and curvature. This method can be implemented either manually or automatically and it produces large area patterns with the quality obtained by the state-of-the-art colloidal lithography at a very high throughput. We first demonstrated the fabrication of nanopatterns with a periodicity ranging between 200 nm and 2 μm. We then demonstrated two nanotechnological applications of this approach. The first one is antireflective structures, fabricated on silicon and sapphire, with different geometries including arrays of bumps and holes and adjusted for different spectral ranges. The second one is smart 3D nanostructures for mechanostimulation of T cells that are used for their effective proliferation, with potential application in cancer immunotherapy. This new approach unleashes the potential of bottom-up nanofabrication and paves the way for nanoscale devices and systems in numerous applications.
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Affiliation(s)
- Sivan Tzadka
- Department of Materials Engineering, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Carlos Ureña Martin
- Department of Materials Engineering, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Esti Toledo
- Department of Materials Engineering, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Abed Al Kader Yassin
- The Shraga Segal Department of Microbiology, Immunology, and Genetics Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Ashish Pandey
- Department of Materials Engineering, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Guillaume Le Saux
- Department of Materials Engineering, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Angel Porgador
- The Shraga Segal Department of Microbiology, Immunology, and Genetics Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
| | - Mark Schvartzman
- Department of Materials Engineering, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
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3
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Shen Q, Jin B, Li J, Sun Z, Kang W, Li H, Jia H, Li Q, Xue J. In-situ construction of TiO 2 polymorphic junction nanoarrays without cocatalyst for boosting photocatalytic hydrogen generation. J Colloid Interface Sci 2024; 653:1630-1641. [PMID: 37812839 DOI: 10.1016/j.jcis.2023.09.198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/12/2023] [Accepted: 09/30/2023] [Indexed: 10/11/2023]
Abstract
There are significant challenges in developing technologies for high-yield photocatalytic hydrogen production reactions. Current photocatalytic materials face three key problems: low utilization of light, rapid recombination of photogenerated electron-hole pairs, and a limited number of active sites during photocatalytic reactions. As a result, these materials only improve one or two of the three steps involved in photocatalytic hydrogen production reactions. Consequently, achieving simultaneous multifunctional synergy to enhance the efficiency of all three processes is difficult. Here, we report an in situ dissolution-recrystallisation approach to design and fabricate a three-dimensional TiO2 rutile/anatase (AE-TiO2) array photocatalytic material for photocatalytic hydrolysis applications. It is shown that the unique 3D nanoarray structure and in situ fabrication of the AE-TiO2 homojunction with synergistic effects among the components lead to an increase in light harvesting efficiency, charge transport separation efficiency and surface active sites, which remarkably improve the photocatalytic hydrolysis performance. The prepared AE-TiO2 homojunction materials realizes a maximal photoactivity of 4 μmol cm-2·h-1, which is 39 times larger than that of pure TiO2 rutile nanorods.
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Affiliation(s)
- Qianqian Shen
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China.
| | - Baobao Jin
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Jinlong Li
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Zhe Sun
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Wenxiang Kang
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Huimin Li
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China
| | - Husheng Jia
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China; Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan 030000, PR China
| | - Qi Li
- School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China
| | - Jinbo Xue
- Key Laboratory of Interface Science and Engineering in Advanced Materials (Taiyuan University of Technology), Ministry of Education, Taiyuan 030024, PR China; College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China.
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4
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Farhadi A, Bartschmid T, Bourret GR. Dewetting-Assisted Patterning: A Lithography-Free Route to Synthesize Black and Colored Silicon. ACS APPLIED MATERIALS & INTERFACES 2023; 15:44087-44096. [PMID: 37669230 PMCID: PMC10520913 DOI: 10.1021/acsami.3c08533] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 08/25/2023] [Indexed: 09/07/2023]
Abstract
We report the use of thermal dewetting to structure gold-based catalytic etching masks for metal-assisted chemical etching (MACE). The approach involves low-temperature dewetting of metal films to generate metal holey meshes with tunable morphologies. Combined with MACE, dewetting-assisted patterning is a simple, benchtop route to synthesize Si nanotubes, Si nanowalls, and Si nanowires with defined dimensions and optical properties. The approach is compatible with the synthesis of both black and colored nanostructured silicon substrates. In particular, we report the lithography-free fabrication of silicon nanowires with diameters down to 40 nm that support leaky wave-guiding modes, giving rise to vibrant colors. Additionally, micrometer-sized areas with tunable film composition and thickness were patterned via shadow masking. After dewetting and MACE, such patterned metal films produced regions with distinct nanostructured silicon morphologies and colors. To-date, the fabrication of colored silicon has relied on complicated nanoscale patterning processes. Dewetting-assisted patterning provides a simpler alternative that eliminates this requirement. Finally, the simple transfer of resonant SiNWs into ethanolic solutions with well-defined light absorption properties is reported. Such solution-dispersible SiNWs could open new avenues for the fabrication of ultrathin optoelectronic devices with enhanced and tunable light absorption.
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Affiliation(s)
- Amin Farhadi
- Department of Chemistry and
Physics of Materials, University of Salzburg, Jakob Haringerstraße 2a, A-5020 Salzburg, Austria
| | - Theresa Bartschmid
- Department of Chemistry and
Physics of Materials, University of Salzburg, Jakob Haringerstraße 2a, A-5020 Salzburg, Austria
| | - Gilles R. Bourret
- Department of Chemistry and
Physics of Materials, University of Salzburg, Jakob Haringerstraße 2a, A-5020 Salzburg, Austria
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5
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Handford RC, Nguyen TT, Teat SJ, Britt RD, Tilley TD. Direct Transformation of SiH 4 to a Molecular L(H) 2Co═Si═Co(H) 2L Silicide Complex. J Am Chem Soc 2023; 145:3031-3039. [PMID: 36696099 DOI: 10.1021/jacs.2c11569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The synthesis of bimetallic molecular silicide complexes is reported, based on the use of multiple Si-H bond activations in SiH4 at the metal centers of 14-electron LCoI fragments (L = Tp″, HB(3,5-diisopropylpyrazolyl)3-; [BP2tBuPz], PhB(CH2PtBu2)2(pyrazolyl)). Upon exposure of (Tp″Co)2(μ-N2) (1) to SiH4, a mixture of (Tp″Co)2(μ-H) (2) and (Tp″Co)2(μ-H)2 (3) was formed and no evidence for Si-H oxidative addition products was observed. In contrast, [BP2tBuPz]-supported Co complexes led to Si-H oxidative additions with the generation of silylene and silicide complexes as products. Notably, the reaction of ([BP2tBuPz]Co)2(μ-N2) (5) with SiH4 gave the dicobalt silicide complex [BP2tBuPz](H)2Co═Si═Co(H)2[BP2tBuPz] (8) in high yield, representing the first direct route to a symmetrical bimetallic silicide. The effect of the [BP2tBuPz] ligand on Co-Si bonding in 7 and 8 was explored by analysis of solid-state molecular structures and density functional theory (DFT) investigations. Upon exposure to CO or DMAP (DMAP = 4-dimethylaminopyridine), 8 converted to the corresponding [BP2tBuPz]Co(L)x adducts (L = CO, x = 2; L = DMAP, x = 1) with concomitant loss of SiH4, despite the lack of significant Si-H interactions in the starting complex. On heating to 60 °C, 8 underwent reaction with MeCl to produce small quantities of MexSiH4-x (x = 1-3), demonstrating functionalization of the μ-silicon atom in a molecular silicide to form organosilanes.
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Affiliation(s)
- Rex C Handford
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | - Trisha T Nguyen
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - Simon J Teat
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - R David Britt
- Department of Chemistry, University of California, Davis, Davis, California 95616, United States
| | - T Don Tilley
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
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6
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Hernández Rodríguez C, Pérez Bueno JDJ, Maldonado Pérez AX, Ruiz Flores M, Oza G. Photoelectrocatalytic activity of silicon nanowires decorated with electroless copper nanoparticles and graphene oxide using a plasma jet for removal of methyl orange under visible light †. RSC Adv 2023; 13:10621-10635. [PMID: 37021106 PMCID: PMC10069624 DOI: 10.1039/d3ra00932g] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 03/28/2023] [Indexed: 04/05/2023] Open
Abstract
Silicon nanowires (SiNWs) have been studied due to their interesting properties, such as light trapping and catalytic activity for removing organic molecules. In this work, silicon nanowires are decorated with copper (SiNWs-CuNPs), graphene oxide (SiNWs-GO), and both copper and graphene oxide GO (SiNWs-CuNPs-GO). They were prepared and tested as photoelectrocatalysts to remove the azoic dye methyl orange (MO). The silicon nanowires were synthesized by the MACE process using HF/AgNO3 solution. The decoration with copper nanoparticles was made by galvanic displacement reaction utilizing a copper sulfate/HF solution, while decoration with GO was achieved using an atmospheric pressure plasma jet system (APPJ). The as-produced nanostructures were then characterized by SEM, XRD, XPS, and Raman spectroscopy. Cu(i) oxide was generated during the decoration with copper. Cu(ii) oxide was produced when SiNWs–CuNPs were exposed to the APPJ. GO was successfully attached on the surface of silicon nanowires and silicon nanowires decorated with copper nanoparticles. The photoelectrocatalytic activity of silicon nanostructures was tested under visible light, leading to an MO removal efficiency of 96% within 175 min with SiNWs–CuNPs-GO, followed by SiNWs-CuNPs, SiNWs-GO, undecorated SiNWs, and bulk silicon. Silicon nanowires (SiNWs) have been studied due to their interesting properties, such as light trapping and catalytic activity for removing organic molecules.![]()
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Affiliation(s)
- Carlos Hernández Rodríguez
- Centro de Investigación y Desarrollo Tecnológico en Electroquímica, S. C. Parque Tecnológico Querétaro – SanfandilaPedro EscobedoQuerétaro76703Mexico
| | - José de Jesús Pérez Bueno
- Centro de Investigación y Desarrollo Tecnológico en Electroquímica, S. C. Parque Tecnológico Querétaro – SanfandilaPedro EscobedoQuerétaro76703Mexico
| | - Alejandra Xochitl Maldonado Pérez
- Centro de Investigación y Desarrollo Tecnológico en Electroquímica, S. C. Parque Tecnológico Querétaro – SanfandilaPedro EscobedoQuerétaro76703Mexico
| | - Missael Ruiz Flores
- Tecnológico de Estudios Superiores de San Felipe del Progreso, Av. Tecnológico s/n, Ejido TecnológicoSan Felipe del ProgresoEstado de México50640Mexico
| | - Goldie Oza
- Centro de Investigación y Desarrollo Tecnológico en Electroquímica, S. C. Parque Tecnológico Querétaro – SanfandilaPedro EscobedoQuerétaro76703Mexico
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7
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Cortés E, Wendisch FJ, Sortino L, Mancini A, Ezendam S, Saris S, de S. Menezes L, Tittl A, Ren H, Maier SA. Optical Metasurfaces for Energy Conversion. Chem Rev 2022; 122:15082-15176. [PMID: 35728004 PMCID: PMC9562288 DOI: 10.1021/acs.chemrev.2c00078] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Nanostructured surfaces with designed optical functionalities, such as metasurfaces, allow efficient harvesting of light at the nanoscale, enhancing light-matter interactions for a wide variety of material combinations. Exploiting light-driven matter excitations in these artificial materials opens up a new dimension in the conversion and management of energy at the nanoscale. In this review, we outline the impact, opportunities, applications, and challenges of optical metasurfaces in converting the energy of incoming photons into frequency-shifted photons, phonons, and energetic charge carriers. A myriad of opportunities await for the utilization of the converted energy. Here we cover the most pertinent aspects from a fundamental nanoscopic viewpoint all the way to applications.
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Affiliation(s)
- Emiliano Cortés
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany,
| | - Fedja J. Wendisch
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany
| | - Luca Sortino
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany
| | - Andrea Mancini
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany
| | - Simone Ezendam
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany
| | - Seryio Saris
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany
| | - Leonardo de S. Menezes
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany,Departamento
de Física, Universidade Federal de
Pernambuco, 50670-901 Recife, Pernambuco, Brazil
| | - Andreas Tittl
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany
| | - Haoran Ren
- MQ Photonics
Research Centre, Department of Physics and Astronomy, Macquarie University, Macquarie
Park, New South Wales 2109, Australia
| | - Stefan A. Maier
- Chair
in Hybrid Nanosystems, Nano Institute Munich, Faculty of Physics, Ludwig-Maximilians-University Munich, Königinstraße 10, 80539 Munich, Germany,School
of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia,Department
of Phyiscs, Imperial College London, London SW7 2AZ, United Kingdom,
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8
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Bartschmid T, Farhadi A, Musso ME, Goerlitzer ESA, Vogel N, Bourret GR. Self-Assembled Au Nanoparticle Monolayers on Silicon in Two- and Three-Dimensions for Surface-Enhanced Raman Scattering Sensing. ACS APPLIED NANO MATERIALS 2022; 5:11839-11851. [PMID: 36062062 PMCID: PMC9425434 DOI: 10.1021/acsanm.2c01904] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/03/2022] [Indexed: 05/05/2023]
Abstract
Gold nanoparticle/silicon composites are canonical substrates for sensing applications because of their geometry-dependent physicochemical properties and high sensing activity via surface-enhanced Raman spectroscopy (SERS). The self-assembly of gold nanoparticles (AuNPs) synthesized via wet-chemistry on functionalized flat silicon (Si) and vertically aligned Si nanowire (VA-SiNW) arrays is a simple and cost-effective approach to prepare such substrates. Herein, we report on the critical parameters that influence nanoparticle coverage, aggregation, and assembly sites in two- and three-dimensions to prepare substrates with homogeneous optical properties and SERS activity. We show that the degree of AuNP aggregation on flat Si depends on the silane used for the Si functionalization, while the AuNP coverage can be adjusted by the incubation time in the AuNP solution, both of which directly affect the substrate properties. In particular, we report the reproducible synthesis of nearly touching AuNP chain monolayers where the AuNPs are separated by nanoscale gaps, likely to be formed due to the capillary forces generated during the drying process. Such substrates, when used for SERS sensing, produce a uniform and large enhancement of the Raman signal due to the high density of hot spots that they provide. We also report the controlled self-assembly of AuNPs on VA-SiNW arrays, which can provide even higher Raman signal enhancement. The directed assembly of the AuNPs in specific regions of the SiNWs with a control over NP density and monolayer morphology (i.e., isolated vs nearly touching NPs) is demonstrated, together with its influence on the resulting SERS activity.
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Affiliation(s)
- Theresa Bartschmid
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, 5020 Salzburg, Austria
| | - Amin Farhadi
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, 5020 Salzburg, Austria
| | - Maurizio E. Musso
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, 5020 Salzburg, Austria
| | - Eric Sidney Aaron Goerlitzer
- Institute
of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Nicolas Vogel
- Institute
of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Gilles R. Bourret
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, 5020 Salzburg, Austria
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9
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Electrochemical Synthesis of Plasmonic Nanostructures. Molecules 2022; 27:molecules27082485. [PMID: 35458688 PMCID: PMC9027786 DOI: 10.3390/molecules27082485] [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: 02/24/2022] [Revised: 04/01/2022] [Accepted: 04/08/2022] [Indexed: 11/23/2022] Open
Abstract
Thanks to their tunable and strong interaction with light, plasmonic nanostructures have been investigated for a wide range of applications. In most cases, controlling the electric field enhancement at the metal surface is crucial. This can be achieved by controlling the metal nanostructure size, shape, and location in three dimensions, which is synthetically challenging. Electrochemical methods can provide a reliable, simple, and cost-effective approach to nanostructure metals with a high degree of geometrical freedom. Herein, we review the use of electrochemistry to synthesize metal nanostructures in the context of plasmonics. Both template-free and templated electrochemical syntheses are presented, along with their strengths and limitations. While template-free techniques can be used for the mass production of low-cost but efficient plasmonic substrates, templated approaches offer an unprecedented synthetic control. Thus, a special emphasis is given to templated electrochemical lithographies, which can be used to synthesize complex metal architectures with defined dimensions and compositions in one, two and three dimensions. These techniques provide a spatial resolution down to the sub-10 nanometer range and are particularly successful at synthesizing well-defined metal nanoscale gaps that provide very large electric field enhancements, which are relevant for both fundamental and applied research in plasmonics.
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