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Cherian Lukose C, Anestopoulos I, Panayiotidis MI, Birkett M. Nanomechanical and Microstructural Characterization of Biocompatible Ti 3Au Thin Films Grown on Glass and Ti 6Al 4V Substrates. ACS Biomater Sci Eng 2024; 10:2935-2944. [PMID: 38627890 PMCID: PMC11094675 DOI: 10.1021/acsbiomaterials.4c00070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 04/09/2024] [Accepted: 04/09/2024] [Indexed: 05/14/2024]
Abstract
Ti-Au intermetallic-based material systems are being extensively studied as next-generation thin film coatings to extend the lifetime of implant devices. These coatings are being developed for application to the articulating surfaces of total joint implants and, therefore, must have excellent biocompatibility combined with superior mechanical hardness and wear resistance. However, these key characteristics of Ti-Au coatings are heavily dependent upon factors such as the surface properties and temperature of the underlying substrate during thin film deposition. In this work, Ti3Au thin films were deposited by magnetron sputtering on both glass and Ti6Al4V substrates at an ambient and elevated substrate temperature of 275 °C. These films were studied for their mechanical properties by the nanoindentation technique in both variable load and fixed load mode using a Berkovich tip. XRD patterns and cross-sectional SEM images detail the microstructure, while AFM images present the surface morphologies of these Ti3Au thin films. The biocompatibility potential of the films is assessed by cytotoxicity tests in L929 mouse fibroblast cells using Alamar blue assay, while leached ion concentrations in the film extracts are quantified using ICPOEMS. The standard deviation for hardness of films deposited on glass substrates is ∼4 times lower than that on Ti6Al4V substrates and is correlated with a corresponding increase in surface roughness from 2 nm for glass to 40 nm for Ti6Al4V substrates. Elevating substrate temperature leads to an increase in film hardness from 5.1 to 8.9 GPa and is related to the development of a superhard β phase of the Ti3Au intermetallic. The standard deviation of this peak mechanical hardness value is reduced by ∼3 times when measured in fixed load mode compared to the variable load mode due to the effect of nanoindentation tip penetration depth. All tested Ti-Au thin films also exhibit excellent biocompatibility against L929 fibroblast cells, as viability levels are above 95% and leached Ti, Al, V, and Au ion concentrations are below 0.1 ppm. Overall, this work demonstrates a novel Ti3Au thin film system with a unique combination of high hardness and excellent biocompatibility with potential to be developed into a new wear-resistant coating to extend the lifetime of articulating total joint implants.
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Affiliation(s)
- Cecil Cherian Lukose
- Department
of Mechanical and Construction Engineering, Northumbria University, Ellison place, Newcastle upon Tyne NE1 8ST, U.K.
| | - Ioannis Anestopoulos
- Department
of Cancer Genetics, Therapeutics & Ultrastructural Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia 1683, Cyprus
| | - Mihalis I. Panayiotidis
- Department
of Cancer Genetics, Therapeutics & Ultrastructural Pathology, The Cyprus Institute of Neurology and Genetics, Nicosia 1683, Cyprus
| | - Martin Birkett
- Department
of Mechanical and Construction Engineering, Northumbria University, Ellison place, Newcastle upon Tyne NE1 8ST, U.K.
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Wittstock G, Bäumer M, Dononelli W, Klüner T, Lührs L, Mahr C, Moskaleva LV, Oezaslan M, Risse T, Rosenauer A, Staubitz A, Weissmüller J, Wittstock A. Nanoporous Gold: From Structure Evolution to Functional Properties in Catalysis and Electrochemistry. Chem Rev 2023; 123:6716-6792. [PMID: 37133401 DOI: 10.1021/acs.chemrev.2c00751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Nanoporous gold (NPG) is characterized by a bicontinuous network of nanometer-sized metallic struts and interconnected pores formed spontaneously by oxidative dissolution of the less noble element from gold alloys. The resulting material exhibits decent catalytic activity for low-temperature, aerobic total as well as partial oxidation reactions, the oxidative coupling of methanol to methyl formate being the prototypical example. This review not only provides a critical discussion of ways to tune the morphology and composition of this material and its implication for catalysis and electrocatalysis, but will also exemplarily review the current mechanistic understanding of the partial oxidation of methanol using information from quantum chemical studies, model studies on single-crystal surfaces, gas phase catalysis, aerobic liquid phase oxidation, and electrocatalysis. In this respect, a particular focus will be on mechanistic aspects not well understood, yet. Apart from the mechanistic aspects of catalysis, best practice examples with respect to material preparation and characterization will be discussed. These can improve the reproducibility of the materials property such as the catalytic activity and selectivity as well as the scope of reactions being identified as the main challenges for a broader application of NPG in target-oriented organic synthesis.
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Affiliation(s)
- Gunther Wittstock
- Carl von Ossietzky University of Oldenburg, School of Mathematics and Science, Institute of Chemistry, D-26111 Oldenburg, Germany
| | - Marcus Bäumer
- University of Bremen, Institute for Applied and Physical Chemistry, 28359 Bremen, Germany
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
| | - Wilke Dononelli
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Bremen Center for Computational Materials Science, Hybrid Materials Interfaces Group, Am Fallturm 1, Bremen 28359, Germany
| | - Thorsten Klüner
- Carl von Ossietzky University of Oldenburg, School of Mathematics and Science, Institute of Chemistry, D-26111 Oldenburg, Germany
| | - Lukas Lührs
- Hamburg University of Technology, Institute of Materials Physics and Technology, 21703 Hamburg, Germany
| | - Christoph Mahr
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute of Solid State Physics, Otto Hahn Allee 1, 28359 Bremen, Germany
| | - Lyudmila V Moskaleva
- University of the Free State, Department of Chemistry, P.O. Box 339, Bloemfontein 9300, South Africa
| | - Mehtap Oezaslan
- Technical University of Braunschweig Institute of Technical Chemistry, Technical Electrocatalysis Laboratory, Franz-Liszt-Strasse 35a, 38106 Braunschweig, Germany
| | - Thomas Risse
- Freie Universität Berlin, Institute of Chemistry and Biochemistry, Arnimallee 22, 14195 Berlin, Germany
| | - Andreas Rosenauer
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute of Solid State Physics, Otto Hahn Allee 1, 28359 Bremen, Germany
| | - Anne Staubitz
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute for Organic and Analytical Chemistry, Leobener Strasse 7, D-28359 Bremen, Germany
| | - Jörg Weissmüller
- Hamburg University of Technology, Institute of Materials Physics and Technology, 21703 Hamburg, Germany
- Helmholtz-Zentrum Hereon, Institute of Materials Mechanics, 21502 Geesthacht, Germany
| | - Arne Wittstock
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute for Organic and Analytical Chemistry, Leobener Strasse 7, D-28359 Bremen, Germany
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Qin Y, Fang D, Wu Y, Wu Y, Yao W. Controllable Preparation of Gold Nanocrystals with Different Porous Structures for SERS Sensing. Molecules 2023; 28:molecules28052316. [PMID: 36903564 PMCID: PMC10004769 DOI: 10.3390/molecules28052316] [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: 02/15/2023] [Revised: 02/28/2023] [Accepted: 03/01/2023] [Indexed: 03/06/2023] Open
Abstract
Porous Au nanocrystals (Au NCs) have been widely used in catalysis, sensing, and biomedicine due to their excellent localized surface plasma resonance effect and a large number of active sites exposed by three-dimensional internal channels. Here, we developed a ligand-induced one-step method for the controllable preparation of mesoporous, microporous, and hierarchical porous Au NCs with internal 3D connecting channels. At 25 °C, using glutathione (GTH) as both a ligand and reducing agent combined with the Au precursor to form GTH-Au(I), and under the action of the reducing agent ascorbic acid, the Au precursor is reduced in situ to form a dandelion-like microporous structure assembled by Au rods. When cetyltrimethylammonium bromide (C16TAB) and GTH are used as ligands, mesoporous Au NCs formed. When increasing the reaction temperature to 80 °C, hierarchical porous Au NCs with both microporous and mesoporous structures will be synthesized. We systematically explored the effect of reaction parameters on porous Au NCs and proposed possible reaction mechanisms. Furthermore, we compared the SERS-enhancing effect of Au NCs with three different pore structures. With hierarchical porous Au NCs as the SERS base, the detection limit for rhodamine 6G (R6G) reached 10-10 M.
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Park S, Nguyen DV, Kang L. Immobilized nanoneedle-like structures for intracellular delivery, biosensing and cellular surgery. Nanomedicine (Lond) 2021; 16:335-349. [PMID: 33533658 DOI: 10.2217/nnm-2020-0337] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The rapid advancements of nanotechnology over the recent years have reformed the methods used for treating human diseases. Nanostructures including nanoneedles, nanorods, nanowires, nanofibers and nanotubes have exhibited their potential roles in drug delivery, biosensing, cancer therapy, regenerative medicine and intracellular surgery. These high aspect ratio structures enhance targeted drug delivery with spatiotemporal control while also demonstrating their role as an efficient intracellular biosensor with minimal invasiveness. This review discusses the history and emergence of these nanostructures and their fabrication methods. This review also provides an overview of the different applications of nanoneedle systems, further highlighting the importance of greater investigation into these nanostructures for future medicine.
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Affiliation(s)
- Sol Park
- School of Pharmacy, Faculty of Medicine & Health, University of Sydney, NSW 2006, Australia
| | - Duc-Viet Nguyen
- Nusmetics Pte. Ltd, i4 building, 3 Research Link, Singapore 117602, Republic of Singapore
| | - Lifeng Kang
- School of Pharmacy, Faculty of Medicine & Health, University of Sydney, NSW 2006, Australia
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Chauvin A, Sergievskaya A, El Mel AA, Fucikova A, Antunes Corrêa C, Vesely J, Duverger-Nédellec E, Cornil D, Cornil J, Tessier PY, Dopita M, Konstantinidis S. Co-sputtering of gold and copper onto liquids: a route towards the production of porous gold nanoparticles. NANOTECHNOLOGY 2020; 31:455303. [PMID: 32726767 DOI: 10.1088/1361-6528/abaa75] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Effective methods for the synthesis of high-purity nanoparticles (NPs) have been extensively studied for a few decades. Among others, cold plasma-based sputtering metals onto a liquid substrate appears to be a very promising technique for the synthesis of high-purity NPs. The process enables the production of very small NPs without using any toxic reagents and complex chemical synthesis routes, and enables the synthesis of alloy NPs which can be the first step towards the formation of porous NPs. In this paper, the synthesis of gold-copper alloy NPs has been performed by co-sputtering gold and copper targets over pentaerythritol ethoxylate. The resulting solutions contain a mixture of gold, copper oxide, and alloy NPs having a radius of few angstroms. The annealing of these NPs, inside the solution, has been performed in order to increase their size and further induce the dealloying of the Au-Cu NPs. The resulting NPs exhibit either a nanoporous structure or are self-organized in an agglomerate of small NPs.
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Affiliation(s)
- Adrien Chauvin
- Department of Condensed Matter Physics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 121 16, Praha 2, Czech Republic
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Abstract
In recent years, the field of nanoporous metals has undergone accelerated developments as these materials possess high specific surface areas, well-defined pore sizes, functional sites, and a wide range of functional properties. Nanoporous gold (NPG) is, surely, the most attractive system in the class of nanoporous metals: it combines several desired characteristics as occurrence of surface plasmon resonances, enormous surface area, electrochemical activity, biocompatibility, in addition to feasibility in preparation. All these properties concur in the exploitatiton of NPG as an efficient and versatile sensong platform. In this regard, NPG-based sensors have shown exceptional sensitivity and selectivity to a wide range of analytes ranging from molecules to biomolecules (and until the single molecule detection) and the enormous surface/volume ratio was shown to be crucial in determining these performances. Thanks to these characteristics, NPG-based sensors are finding applications in medical, biological, and safety fields so as in medical diagnostics and monitoring processes. So, a rapidly growing literature is currently investigating the properties of NPG systems toward the detection of a multitude of classes of analytes highlighting strengths and limits. Due to the extension, complexity, and importance of this research field, in the present review we attempt, starting from the discussion of specific cases, to focus our attention on the basic properties of NPG in connection to the main sensing applications, i.e., surface enhanced Raman spectroscopy-based and electrochemical-based sensing. Owing to the nano-sized pore channels and Au ligaments, which are much smaller than the wavelength of visible light (400–700 nm), surface plasmon resonances of NPG can be effectively excited by visible light and presents unique features compared with other nanostructured metals, such as nanoparticles, nanorods, and nanowires. This characteristics leads to optical sensors exploiting NPG through unique surface plasmon resonance properties that can be monitored by UV-Vis, Raman, or fluorescence spectroscopy. On the other hand, the catalytic properties of NPG are exploited electrochemical sensors are on the electrical signal produced by a specific analyte adsorbed of the NPG surface. In this regard, the enourmous NPG surface area is crucial in determining the sensitivity enhancement. Due to the extension, complexity, and importance of the NPG-based sensing field, in the present review we attempt, starting from the discussion of specific cases, to focus our attention on the basic properties of NPG in connection to the main sensing applications, i.e., surface enhanced Raman spectroscopy-based and electrochemical-based sensing. Starting from the discussion of the basic morphological/structural characteristics of NPG as obtained during the fabrication step and post-fabrication processes, the review aims to a comprehensive schematization of the main classes of sensing applications highlighting the basic involved physico-chemical properties and mechanisms. In each discussed specific example, the main involved parameters and processes governing the sensing mechanism are elucidated. In this way, the review aims at establishing a general framework connecting the processes parameters to the characteristics (pore size, etc.) of the NPG. Some examples are discussed concerning surface plasmon enhanced Uv-Vis, Raman, fluorescence spectroscopy in order to realize efficient NPG-based optical sesnors: in this regard, the underlaying connections between NPG structural/morphological properties and the optical response and, hence, the optical-based sensing performances are described and analyzed. Some other examples are discussed concerning the exploitation of the electrochemical characteristics of NPG for ultra-high sensitivity detection of analytes: in this regard, the key parameters determing the NPG activity and selectivity selectivity toward a variety of reactants are discussed, as high surface-to-volume ratio and the low coordination of surface atoms. In addition to the use of standard NPG films and leafs as sensing platforms, also the role of hybrid NPG-based nanocomposites and of nanoporous Au nanostructures is discussed due to the additional increase of the electrocatalytic acticvity and of exposed surface area resulting in the possible further sensitivity increase.
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Kashefi-Kheyrabadi L, Koyappayil A, Kim T, Cheon YP, Lee MH. A MoS 2@Ti 3C 2T x MXene hybrid-based electrochemical aptasensor (MEA) for sensitive and rapid detection of Thyroxine. Bioelectrochemistry 2020; 137:107674. [PMID: 32949936 DOI: 10.1016/j.bioelechem.2020.107674] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/07/2020] [Accepted: 09/07/2020] [Indexed: 12/13/2022]
Abstract
In the present study, a MoS2@Ti3C2Tx MXene hybrid-based electrochemical aptasensor (MEA) was introduced for sensitive and rapid quantification of Thyroxine (T4). T4 is a crucial hormone and plays a key role in various body functions. Therefore, there is high demand for an accurate, sensitive, and rapid method for the detection of T4. To construct the aptasensor, a nano-hybrid (NH) consisting of Ti3C2Tx MXene and MoS2 nanosheets (NS) was synthesized, and applied to a carbon electrode surface, followed by the electroplating of gold nanostructures (GN). The smart combination of Ti3C2Tx MXene and MoS2NS enhanced the physiochemical properties of the electrode surface, as well as provided a building block to form 3D GN. The 3D architecture of the GN offered a unique substrate to capture numerous T4 aptamer molecules, which consequently amplified the signal by nearly 6-fold. The MEA quantified thyroxine with a limit of detection (LOD) of 0.39 pg/mL over a dynamic range ((7.8 × 10-1) to (7.8 × 106)) pg/mL within 10 min. Moreover, the MEA successfully detected T4 in human serum samples. Lastly, the results obtained from the aptasensor were compared with those from the ELISA standard method. The comparative analysis showed good agreement between the two methods.
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Affiliation(s)
- Leila Kashefi-Kheyrabadi
- School of Integrative Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Aneesh Koyappayil
- School of Integrative Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Taeeun Kim
- Division of Developmental Biology and Physiology, Department of Biotechnology, Institute for Basic Sciences, Sungshin University, Seoul 02844, Republic of Korea
| | - Yong-Pil Cheon
- Division of Developmental Biology and Physiology, Department of Biotechnology, Institute for Basic Sciences, Sungshin University, Seoul 02844, Republic of Korea
| | - Min-Ho Lee
- School of Integrative Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea
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8
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Chauvin A, Lafuente M, Mevellec JY, Mallada R, Humbert B, Pina MP, Tessier PY, El Mel A. Lamellar nanoporous gold thin films with tunable porosity for ultrasensitive SERS detection in liquid and gas phase. NANOSCALE 2020; 12:12602-12612. [PMID: 32501469 DOI: 10.1039/d0nr01721c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Lamellar nanoporous gold thin films, constituted of a stack of very thin layers of porous gold, are synthesized by chemical etching from a stack of successively deposited nanolayers of copper and gold. The gold ligament size, the pore size and the distance between lamellas are tunable in the few tens nanometer range by controlling the initial thickness of the layers and the etching time. The SERS activity of these lamellar porous gold films is characterized by their SERS responses after adsorption of probe bipyridine and naphtalenethiol molecules. The SERS signal is investigated as a function of the bipyridine concentration from 10-14 mol L-1 to 10-3 mol L-1. The higher SERS response corresponds to an experimental detection limit down to 10-12 mol L-1. These performance is mainly attributed to the specific nanoporous gold architecture and the larger accessible surface to volume ratio. The lamellar nanoporous gold substrate is explored for sensitive SERS detection of dimethyl methylphosphonate (DMMP), a surrogate molecule of the highly toxic G-series nerve agents. The resultant nanostructure facilitates the diffusion of target molecules through the nanopores and their localization at the enhancing metallic surface leading to the unequivocal Raman signature of DMMP at a concentration of 5 parts per million.
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Affiliation(s)
- Adrien Chauvin
- Institut des Matériaux Jean Rouxel, IMN, Université de Nantes, CNRS, 2 rue de la Houssinière B.P. 32229, 44322 Nantes cedex 3, France.
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Bollella P. Porous Gold: A New Frontier for Enzyme-Based Electrodes. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E722. [PMID: 32290306 PMCID: PMC7221854 DOI: 10.3390/nano10040722] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/01/2020] [Accepted: 04/08/2020] [Indexed: 12/23/2022]
Abstract
Porous gold (PG) layers modified electrodes have emerged as valuable enzyme support to realize multiple enzyme-based bioelectrochemical devices like biosensors, enzymatic fuel cells (EFCs), smart drug delivery devices triggered by enzyme catalyzed reactions, etc. PG films can be synthesized by using different methods such as dealloying, electrochemical (e.g., templated electrochemical deposition, self-templated electrochemical deposition, etc.) self-assembly and sputter deposition. This review aims to summarize the recent findings about PG synthesis and electrosynthesis, its characterization and application for enzyme-based electrodes used for biosensors and enzymatic fuel cells (EFCs) development.
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Affiliation(s)
- Paolo Bollella
- Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, 13699-5810 NY, USA
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10
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Wang D, Schaaf P. Synthesis and characterization of size controlled bimetallic nanosponges. PHYSICAL SCIENCES REVIEWS 2019. [DOI: 10.1515/psr-2018-0125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractMetallic and bimetallic nanosponges with well-defined size and form have attracted increasing attention due to their unique structural properties and their potential for many applications. In this chapter, the recently developed methods for the synthesis and preparation of metallic and bimetallic nanosponges are presented. These methods can be mainly cataloged in two groups: dealloying-based methods and reduction reaction-based methods. Different topographical reconstruction methods for the investigation of their structural properties are then reviewed briefly. The optical properties of the metallic nanosponges are clearly different from those of the solid counterparts due to the tailored disordered structure. The recent advances in the exploration of the distinct linear and non-linear optical properties of the nanosponges are summarized.Graphical Abstract:
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Zhan Y, Shu S, Tsang CK, Lee C, Shao Q, Lu J, Li YY. Electrochemically Synthesized Porous Ag Double Layers for Surface-Enhanced Raman Spectroscopy Applications. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:6340-6345. [PMID: 31027421 DOI: 10.1021/acs.langmuir.9b00567] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Double-layered nanoporous silver is fabricated by dealloying an electrodeposited AgCu double layer with different compositions in each layer. The pore/ligament size and porosity of each layer can be conveniently tailored by controlling the applied voltage profile when electrodepositing the AgCu double-layer precursors. Therefore, nanoporous Ag double layers with a tailor-made porous profile along the film thickness can be easily fabricated. The Ag structures thus obtained are particularly attractive as novel multifunctional enhancement substrates for surface-enhanced Raman spectroscopy (SERS) applications. When a higher porosity is created in the top layer, the double layer can trap more light because of the antireflection effect, enabling stronger SERS enhancement. On the other hand, with smaller pores formed in the top layer, the double layer readily works as a size-screening SERS substrate that can help distinguish SERS signals from a mixture of reagents with different sizes. The theoretical simulation shows good agreement with the experimental observation.
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Affiliation(s)
- Yawen Zhan
- Hong Kong Branch of National Precious Metals Material Engineering Research Centre , City University of Hong Kong , Kowloon 999077 , Hong Kong , China
| | - Shiwei Shu
- Hong Kong Branch of National Precious Metals Material Engineering Research Centre , City University of Hong Kong , Kowloon 999077 , Hong Kong , China
| | - Chun-Kwan Tsang
- Hong Kong Branch of National Precious Metals Material Engineering Research Centre , City University of Hong Kong , Kowloon 999077 , Hong Kong , China
| | - Chris Lee
- Hong Kong Branch of National Precious Metals Material Engineering Research Centre , City University of Hong Kong , Kowloon 999077 , Hong Kong , China
| | - Qingguo Shao
- Hong Kong Branch of National Precious Metals Material Engineering Research Centre , City University of Hong Kong , Kowloon 999077 , Hong Kong , China
| | - Jian Lu
- Hong Kong Branch of National Precious Metals Material Engineering Research Centre , City University of Hong Kong , Kowloon 999077 , Hong Kong , China
- Centre for Advanced Structural Materials , City University of Hong Kong Shenzhen Research Institute , 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park , Nanshan District, Shenzhen 518000 , China
| | - Yang Yang Li
- Hong Kong Branch of National Precious Metals Material Engineering Research Centre , City University of Hong Kong , Kowloon 999077 , Hong Kong , China
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Evolution of Nanoporous Surface Layers on Gas-Atomized Ti 60Cu 39Au₁ Powders during Dealloying. NANOMATERIALS 2018; 8:nano8080581. [PMID: 30061477 PMCID: PMC6116246 DOI: 10.3390/nano8080581] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Revised: 07/19/2018] [Accepted: 07/23/2018] [Indexed: 01/05/2023]
Abstract
Nanoporous golf ball-shaped powders with a surface porous layer consisting of fcc Cu and Cu3Au phases have been fabricated by selectively dissolving gas-atomized Ti60Cu39Au1 powders in 0.13 M HF solution. The distribution profiles of the Ti2Cu and TiCu intermetallic phases and powder size play an important role of the propagation of the selective corrosion frontiers. The final nanoporous structure has a bimodal characteristic with a finer nanoporous structure at the ridges, and rougher structure at the shallow pits. The powders with a size of 18–75 m dealloy faster due to their high crystallinity and larger powder size, and these with a powder size of smaller than 18 m tend to deepen uniformly. The formation of the Cu3Au intermetallic phases and the finer nanoporous structure at the ridges proves that minor Au addition inhibits the fast diffusion of Cu adatoms and decreases surface diffusion by more than two orders. The evolution of the surface nanoporous structure with negative tree-like structures is considered to be controlled by a percolation dissolution mechanism.
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13
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Current development of 1D and 2D metallic nanomaterials for the application of transparent conductors in solar cells: Fabrication and modeling. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.nanoso.2017.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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14
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Gaining new insights into nanoporous gold by mining and analysis of published images. Sci Rep 2018; 8:6761. [PMID: 29712970 PMCID: PMC5928227 DOI: 10.1038/s41598-018-25122-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 04/03/2018] [Indexed: 11/16/2022] Open
Abstract
One way of expediting materials development is to decrease the need for new experiments by making greater use of published literature. Here, we use data mining and automated image analysis to gather new insights on nanoporous gold (NPG) without conducting additional experiments or simulations. NPG is a three-dimensional porous network that has found applications in catalysis, sensing, and actuation. We assemble and analyze published images from among thousands of publications on NPG. These images allow us to infer a quantitative description of NPG coarsening as a function of time and temperature, including the coarsening exponent and activation energy. They also demonstrate that relative density and ligament size in NPG are not correlated, indicating that these microstructure features are independently tunable. Our investigation leads us to propose improved reporting guidelines that will enhance the utility of future publications in the field of dealloyed materials.
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15
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Zhang T, Sun Y, Hang L, Li H, Liu G, Zhang X, Lyu X, Cai W, Li Y. Periodic Porous Alloyed Au-Ag Nanosphere Arrays and Their Highly Sensitive SERS Performance with Good Reproducibility and High Density of Hotspots. ACS APPLIED MATERIALS & INTERFACES 2018; 10:9792-9801. [PMID: 29480010 DOI: 10.1021/acsami.7b17461] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Periodic porous alloyed Au-Ag nanosphere (NS) arrays with different periodic lengths and tunable composition ratios were prepared on Si substrates on a large scale (∼cm2) using stepwise metal deposition-annealing and subsequent chemical corrosion from a monolayer of colloidal polystyrene (PS) microspheres as the initial template. The porous alloyed Au-Ag NSs possessed a high porosity and bicontinuous morphology composed of hierarchically interconnected ligaments, which were obtained from an optimized dealloying process in nitric acid. Interestingly, when the dealloying time was prolonged, the average size of the porous alloyed NSs slightly decreased, and the width of the ligaments gradually increased. The periodic length of the array could be facilely changed by controlling the initial particle size of the PS template. Moreover, the porous alloyed Au-Ag NS arrays were explored as a platform for the surface-enhanced Raman scattering (SERS) detection of 4-aminothiophenol (4-ATP) and exhibited excellent reproducibility and high sensitivity because of the periodic structure of the arrays and the abundance of inherent "hotspots". After optimization experiments, a low concentration of 10-10 M 4-ATP could be detected on these porous Au-Ag NS array substrates. Such highly reproducible SERS activity is meaningful for improving the practical application of portable Raman detection equipment.
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Affiliation(s)
- Tao Zhang
- Key Lab of Materials Physics, Anhui Key Lab of Nanomaterials and Nanotechnology, Institute of Solid State Physics , Chinese Academy of Sciences , Hefei 230031 , P. R. China
- University of Science and Technology of China , Hefei 230026 , P. R. China
| | - Yiqiang Sun
- Key Lab of Materials Physics, Anhui Key Lab of Nanomaterials and Nanotechnology, Institute of Solid State Physics , Chinese Academy of Sciences , Hefei 230031 , P. R. China
- University of Science and Technology of China , Hefei 230026 , P. R. China
| | - Lifeng Hang
- Key Lab of Materials Physics, Anhui Key Lab of Nanomaterials and Nanotechnology, Institute of Solid State Physics , Chinese Academy of Sciences , Hefei 230031 , P. R. China
| | - Huilin Li
- Key Lab of Materials Physics, Anhui Key Lab of Nanomaterials and Nanotechnology, Institute of Solid State Physics , Chinese Academy of Sciences , Hefei 230031 , P. R. China
- University of Science and Technology of China , Hefei 230026 , P. R. China
| | - Guangqiang Liu
- Key Lab of Materials Physics, Anhui Key Lab of Nanomaterials and Nanotechnology, Institute of Solid State Physics , Chinese Academy of Sciences , Hefei 230031 , P. R. China
| | - Xiaomin Zhang
- College of Materials and Mineral Resources , Xi'an University of Architecture and Technology , Xi'an 710055 , P. R. China
| | - Xianjun Lyu
- College of Chemical and Environmental Engineering , Shandong University of Science and Technology , Qingdao 266590 , P. R. China
| | - Weiping Cai
- Key Lab of Materials Physics, Anhui Key Lab of Nanomaterials and Nanotechnology, Institute of Solid State Physics , Chinese Academy of Sciences , Hefei 230031 , P. R. China
| | - Yue Li
- Key Lab of Materials Physics, Anhui Key Lab of Nanomaterials and Nanotechnology, Institute of Solid State Physics , Chinese Academy of Sciences , Hefei 230031 , P. R. China
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16
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Preparation, Modification, Characterization, and Biosensing Application of Nanoporous Gold Using Electrochemical Techniques. NANOMATERIALS 2018; 8:nano8030171. [PMID: 29547580 PMCID: PMC5869662 DOI: 10.3390/nano8030171] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Revised: 03/13/2018] [Accepted: 03/13/2018] [Indexed: 12/21/2022]
Abstract
Nanoporous gold (np-Au), because of its high surface area-to-volume ratio, excellent conductivity, chemical inertness, physical stability, biocompatibility, easily tunable pores, and plasmonic properties, has attracted much interested in the field of nanotechnology. It has promising applications in the fields of catalysis, bio/chemical sensing, drug delivery, biomolecules separation and purification, fuel cell development, surface-chemistry-driven actuation, and supercapacitor design. Many chemical and electrochemical procedures are known for the preparation of np-Au. Recently, researchers are focusing on easier and controlled ways to tune the pores and ligaments size of np-Au for its use in different applications. Electrochemical methods have good control over fine-tuning pore and ligament sizes. The np-Au electrodes that are prepared using electrochemical techniques are robust and are easier to handle for their use in electrochemical biosensing. Here, we review different electrochemical strategies for the preparation, post-modification, and characterization of np-Au along with the synergistic use of both electrochemistry and np-Au for applications in biosensing.
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17
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Ding J, Fu S, Zhang R, Boon E, Lee W, Fisher FT, Yang EH. Graphene-vertically aligned carbon nanotube hybrid on PDMS as stretchable electrodes. NANOTECHNOLOGY 2017; 28:465302. [PMID: 29064823 DOI: 10.1088/1361-6528/aa8ba9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Stretchable electrodes are a critical component for flexible electronics such as displays, energy devices, and wearable sensors. Carbon nanotubes (CNTs) and graphene have been considered for flexible electrode applications, due to their mechanical strength, high carrier mobility, and excellent thermal conductivity. Vertically aligned carbon nanotubes (VACNTs) provide the possibility to serve as interconnects to graphene sheets as stretchable electrodes that could maintain high electrical conductivity under large tensile strain. In this work, a graphene oxide (GO)-VACNT hybrid on a PDMS substrate was demonstrated. Here, 50 μm long VACNTs were grown on a Si/SiO2 wafer substrate via atmospheric pressure chemical vapor deposition. VACNTs were directly transferred by delamination from the Si/SiO2 to a semi-cured PDMS substrate, ensuring strong adhesion between VACNTs and PDMS upon full curing of the PDMS. GO ink was then printed on the surface of the VACNT carpet and thermally reduced to reduced graphene oxide (rGO). The sheet resistance of the rGO-VACNT hybrid was measured under uniaxial tensile strains up to 300% applied to the substrate. Under applied strain, the rGO-VACNT hybrid maintained a sheet resistant of 386 ± 55 Ω/sq. Cyclic stretching of the rGO-VACNT hybrid was performed with up to 50 cycles at 100% maximum tensile strain, showing no increase in sheet resistance. These results demonstrate promising performance of the rGO-VACNT hybrid for flexible electronics applications.
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Affiliation(s)
- Junjun Ding
- Department of Mechanical Engineering, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030, United States of America
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18
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Large-Scale Fabrication of Porous Gold Nanowires via Laser Interference Lithography and Dealloying of Gold–Silver Nano-Alloys. MICROMACHINES 2017. [PMCID: PMC6190193 DOI: 10.3390/mi8060168] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In this work, we report on an efficient approach to fabricating large-area and uniform planar arrays of highly ordered nanoporous gold nanowires. The approach consists in dealloying Au–Ag alloy nanowires in concentrated nitric acid. The Au–Ag alloy nanowires were obtained by thermal annealing at 800 °C for 2 h of Au/Ag stacked nanoribbons prepared by subsequent evaporation of silver and gold through a nanograted photoresist layer serving as a mask for a lift-off process. Laser interference lithography was employed for the nanopatterning of the photoresist layer to create the large-area nanostructured mask. The result shows that for a low Au-to-Ag ratio of 1, the nanowires tend to cracks during the dealloying due to the internal residual stress generated during the dealloying process, whereas the increase of the Au-to-Ag ratio to 3 can overcome the drawback and successfully leads to the obtainment of an array of highly ordered nanoporous gold nanowires. Nanoporous gold nanowires with such well-regulated organization on a wafer-scale planar substrate are of great significance in many applications including sensors and actuators.
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19
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Du K, Ding J, Liu Y, Wathuthanthri I, Choi CH. Stencil Lithography for Scalable Micro- and Nanomanufacturing. MICROMACHINES 2017. [PMCID: PMC6189734 DOI: 10.3390/mi8040131] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this paper, we review the current development of stencil lithography for scalable micro- and nanomanufacturing as a resistless and reusable patterning technique. We first introduce the motivation and advantages of stencil lithography for large-area micro- and nanopatterning. Then we review the progress of using rigid membranes such as SiNx and Si as stencil masks as well as stacking layers. We also review the current use of flexible membranes including a compliant SiNx membrane with springs, polyimide film, polydimethylsiloxane (PDMS) layer, and photoresist-based membranes as stencil lithography masks to address problems such as blurring and non-planar surface patterning. Moreover, we discuss the dynamic stencil lithography technique, which significantly improves the patterning throughput and speed by moving the stencil over the target substrate during deposition. Lastly, we discuss the future advancement of stencil lithography for a resistless, reusable, scalable, and programmable nanolithography method.
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Affiliation(s)
- Ke Du
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA; (K.D.); (J.D.); (Y.L.); (I.W.)
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
| | - Junjun Ding
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA; (K.D.); (J.D.); (Y.L.); (I.W.)
| | - Yuyang Liu
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA; (K.D.); (J.D.); (Y.L.); (I.W.)
| | - Ishan Wathuthanthri
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA; (K.D.); (J.D.); (Y.L.); (I.W.)
- Northrop Grumman Mission Systems, Advanced Technology Labs, Linthicum, MD 21090, USA
| | - Chang-Hwan Choi
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA; (K.D.); (J.D.); (Y.L.); (I.W.)
- Correspondence: ; Tel.: +1-201-216-5579
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20
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Muench F, Sun L, Kottakkat T, Antoni M, Schaefer S, Kunz U, Molina-Luna L, Duerrschnabel M, Kleebe HJ, Ayata S, Roth C, Ensinger W. Free-Standing Networks of Core-Shell Metal and Metal Oxide Nanotubes for Glucose Sensing. ACS APPLIED MATERIALS & INTERFACES 2017; 9:771-781. [PMID: 27935294 DOI: 10.1021/acsami.6b13979] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Nanotube assemblies represent an emerging class of advanced functional materials, whose utility is however hampered by intricate production processes. In this work, three classes of nanotube networks (monometallic, bimetallic, and metal oxide) are synthesized solely using facile redox reactions and commercially available ion track membranes. First, the disordered pores of an ion track membrane are widened by chemical etching, resulting in the formation of a strongly interconnected pore network. Replicating this template structure with electroless copper plating yields a monolithic film composed of crossing metal nanotubes. We show that the parent material can be easily transformed into bimetallic or oxidic derivatives by applying a second electroless plating or thermal oxidation step. These treatments retain the monolithic network structure but result in the formation of core-shell nanotubes of altered composition (thermal oxidation: Cu2O-CuO; electroless nickel coating: Cu-Ni). The obtained nanomaterials are applied in the enzyme-free electrochemical detection of glucose, showing very high sensitivities between 2.27 and 2.83 A M-1 cm-2. Depending on the material composition, varying reactivities were observed: While copper oxidation reduces the response to glucose, it is increased in the case of nickel modification, albeit at the cost of decreased selectivity. The performance of the materials is explained by the network architecture, which combines the advantages of one-dimensional nano-objects (continuous conduction pathways, high surface area) with those of a self-supporting, open-porous superstructure (binder-free catalyst layer, efficient diffusion). In summary, this novel synthetic approach provides a fast, scalable, and flexible route toward free-standing nanotube arrays of high compositional complexity.
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Affiliation(s)
- Falk Muench
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
| | - Luwan Sun
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
| | - Tintula Kottakkat
- Department of Physical and Theoretical Chemistry, Freie Universität Berlin , Takustraße 3, 14195 Berlin, Germany
| | - Markus Antoni
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
| | - Sandra Schaefer
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
| | - Ulrike Kunz
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
| | - Leopoldo Molina-Luna
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
| | - Michael Duerrschnabel
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
| | - Hans-Joachim Kleebe
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
| | - Sevda Ayata
- Science Faculty, Department of Chemistry, Dokuz Eylul University , Tinaztepe Kampusu, Buca, 35160 Izmir, Turkey
| | - Christina Roth
- Department of Physical and Theoretical Chemistry, Freie Universität Berlin , Takustraße 3, 14195 Berlin, Germany
| | - Wolfgang Ensinger
- Department of Materials and Earth Sciences, Technische Universität Darmstadt , Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany
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21
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Chauvin A, Delacôte C, Boujtita M, Angleraud B, Ding J, Choi CH, Tessier PY, El Mel AA. Dealloying of gold-copper alloy nanowires: From hillocks to ring-shaped nanopores. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2016; 7:1361-1367. [PMID: 27826510 PMCID: PMC5082475 DOI: 10.3762/bjnano.7.127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/09/2016] [Indexed: 06/06/2023]
Abstract
We report on a novel fabrication approach of metal nanowires with complex surface. Taking advantage of nodular growth triggered by the presence of surface defects created intentionally on the substrate as well as the high tilt angle between the magnetron source axis and the normal to the substrate, metal nanowires containing hillocks emerging out of the surface can be created. The approach is demonstrated for several metals and alloys including gold, copper, silver, gold-copper and gold-silver. We demonstrate that applying an electrochemical dealloying process to the gold-copper alloy nanowire arrays allows for transforming the hillocks into ring-like shaped nanopores. The resulting porous gold nanowires exhibit a very high roughness and high specific surface making of them a promising candidate for the development of SERS-based sensors.
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Affiliation(s)
- Adrien Chauvin
- Institut des Matériaux Jean Rouxel, IMN, Université de Nantes, CNRS, 2 rue de la Houssinière B.P. 32229, 44322 Nantes cedex 3, France
| | - Cyril Delacôte
- CEISAM, Université de Nantes, CNRS, 2 rue de la Houssinière B.P. 32229, 44322 Nantes cedex 3, France
| | - Mohammed Boujtita
- CEISAM, Université de Nantes, CNRS, 2 rue de la Houssinière B.P. 32229, 44322 Nantes cedex 3, France
| | - Benoit Angleraud
- Institut des Matériaux Jean Rouxel, IMN, Université de Nantes, CNRS, 2 rue de la Houssinière B.P. 32229, 44322 Nantes cedex 3, France
| | - Junjun Ding
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Chang-Hwan Choi
- Department of Mechanical Engineering, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Pierre-Yves Tessier
- Institut des Matériaux Jean Rouxel, IMN, Université de Nantes, CNRS, 2 rue de la Houssinière B.P. 32229, 44322 Nantes cedex 3, France
| | - Abdel-Aziz El Mel
- Institut des Matériaux Jean Rouxel, IMN, Université de Nantes, CNRS, 2 rue de la Houssinière B.P. 32229, 44322 Nantes cedex 3, France
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22
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Liu K, Bai Y, Zhang L, Yang Z, Fan Q, Zheng H, Yin Y, Gao C. Porous Au-Ag Nanospheres with High-Density and Highly Accessible Hotspots for SERS Analysis. NANO LETTERS 2016; 16:3675-81. [PMID: 27192436 DOI: 10.1021/acs.nanolett.6b00868] [Citation(s) in RCA: 228] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Colloidal plasmonic metal nanoparticles have enabled surface-enhanced Raman scattering (SERS) for a variety of analytical applications. While great efforts have been made to create hotspots for amplifying Raman signals, it remains a great challenge to ensure their high density and accessibility for improved sensitivity of the analysis. Here we report a dealloying process for the fabrication of porous Au-Ag alloy nanoparticles containing abundant inherent hotspots, which were encased in ultrathin hollow silica shells so that the need of conventional organic capping ligands for stabilization is eliminated, producing colloidal plasmonic nanoparticles with clean surface and thus high accessibility of the hotspots. As a result, these novel nanostructures show excellent SERS activity with an enhancement factor of ∼1.3 × 10(7) on a single particle basis (off-resonant condition), promising high applicability in many SERS-based analytical and biomedical applications.
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Affiliation(s)
- Kai Liu
- Center for Materials Chemistry, Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710054, China
| | - Yaocai Bai
- Department of Chemistry, University of California , Riverside, California 92521, United States
| | - Lei Zhang
- Center for Materials Chemistry, Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710054, China
| | - Zhongbo Yang
- Chongqing Key Laboratory of Multi-scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences , Chongqing 400714, China
| | - Qikui Fan
- Center for Materials Chemistry, Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710054, China
| | - Haoquan Zheng
- Department of Materials and Environmental Chemistry, Stockholm University , Stockholm 10691, Sweden
| | - Yadong Yin
- Department of Chemistry, University of California , Riverside, California 92521, United States
| | - Chuanbo Gao
- Center for Materials Chemistry, Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710054, China
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23
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Gentile A, Ruffino F, Grimaldi MG. Complex-Morphology Metal-Based Nanostructures: Fabrication, Characterization, and Applications. NANOMATERIALS 2016; 6:nano6060110. [PMID: 28335236 PMCID: PMC5302633 DOI: 10.3390/nano6060110] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 05/18/2016] [Accepted: 05/21/2016] [Indexed: 11/16/2022]
Abstract
Due to their peculiar qualities, metal-based nanostructures have been extensively used in applications such as catalysis, electronics, photography, and information storage, among others. New applications for metals in areas such as photonics, sensing, imaging, and medicine are also being developed. Significantly, most of these applications require the use of metals in the form of nanostructures with specific controlled properties. The properties of nanoscale metals are determined by a set of physical parameters that include size, shape, composition, and structure. In recent years, many research fields have focused on the synthesis of nanoscale-sized metallic materials with complex shape and composition in order to optimize the optical and electrical response of devices containing metallic nanostructures. The present paper aims to overview the most recent results—in terms of fabrication methodologies, characterization of the physico-chemical properties and applications—of complex-morphology metal-based nanostructures. The paper strongly focuses on the correlation between the complex morphology and the structures’ properties, showing how the morphological complexity (and its nanoscale control) can often give access to a wide range of innovative properties exploitable for innovative functional device production. We begin with an overview of the basic concepts on the correlation between structural and optical parameters of nanoscale metallic materials with complex shape and composition, and the possible solutions offered by nanotechnology in a large range of applications (catalysis, electronics, photonics, sensing). The aim is to assess the state of the art, and then show the innovative contributions that can be proposed in this research field. We subsequently report on innovative, versatile and low-cost synthesis techniques, suitable for providing a good control on the size, surface density, composition and geometry of the metallic nanostructures. The main purpose of this study is the fabrication of functional nanoscale-sized materials, whose properties can be tailored (in a wide range) simply by controlling the structural characteristics. The modulation of the structural parameters is required to tune the plasmonic properties of the nanostructures for applications such as biosensors, opto-electronic or photovoltaic devices and surface-enhanced Raman scattering (SERS) substrates. The structural characterization of the obtained nanoscale materials is employed in order to define how the synthesis parameters affect the structural characteristics of the resulting metallic nanostructures. Then, macroscopic measurements are used to probe their electrical and optical properties. Phenomenological growth models are drafted to explain the processes involved in the growth and evolution of such composite systems. After the synthesis and characterization of the metallic nanostructures, we study the effects of the incorporation of the complex morphologies on the optical and electrical responses of each specific device.
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Affiliation(s)
- Antonella Gentile
- Department of Physics and Astronomy-University of Catania, via S. Sofia 64, 95123 Catania, Italy.
- MATIS IMM-CNR, via S. Sofia 64, 95123 Catania, Italy.
| | - Francesco Ruffino
- Department of Physics and Astronomy-University of Catania, via S. Sofia 64, 95123 Catania, Italy.
- MATIS IMM-CNR, via S. Sofia 64, 95123 Catania, Italy.
| | - Maria Grazia Grimaldi
- Department of Physics and Astronomy-University of Catania, via S. Sofia 64, 95123 Catania, Italy.
- MATIS IMM-CNR, via S. Sofia 64, 95123 Catania, Italy.
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24
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Xu S, Joseph S, Zhang H, Lou J, Lu Y. Controllable high-throughput fabrication of porous gold nanorods driven by Rayleigh instability. RSC Adv 2016. [DOI: 10.1039/c6ra11050a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Porous gold nanorods with uniform diameters can be obtained by dealloying of fragmented Au–Ag nanowires, driven by Rayleigh instability.
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Affiliation(s)
- Shang Xu
- Department of Mechanical and Biomedical Engineering
- City University of Hong Kong
- Kowloon
- China
- Center of Super-Diamond and Advanced Films (COSDAF)
| | - Sona Joseph
- Department of Materials Science and NanoEngineering
- Rice University
- Houston
- USA
- The Methodist Hospital Research Institute
| | - Hongti Zhang
- Department of Mechanical and Biomedical Engineering
- City University of Hong Kong
- Kowloon
- China
| | - Jun Lou
- Department of Materials Science and NanoEngineering
- Rice University
- Houston
- USA
| | - Yang Lu
- Department of Mechanical and Biomedical Engineering
- City University of Hong Kong
- Kowloon
- China
- Center of Super-Diamond and Advanced Films (COSDAF)
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