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Karpets M, Rajnak M, Petrenko V, Gapon I, Avdeev M, Bulavin L, Timko M, Kopcanský P. Electric field-induced assembly of magnetic nanoparticles from dielectric ferrofluids on planar interface. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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2
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Socoliuc V, Avdeev MV, Kuncser V, Turcu R, Tombácz E, Vékás L. Ferrofluids and bio-ferrofluids: looking back and stepping forward. NANOSCALE 2022; 14:4786-4886. [PMID: 35297919 DOI: 10.1039/d1nr05841j] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Ferrofluids investigated along for about five decades are ultrastable colloidal suspensions of magnetic nanoparticles, which manifest simultaneously fluid and magnetic properties. Their magnetically controllable and tunable feature proved to be from the beginning an extremely fertile ground for a wide range of engineering applications. More recently, biocompatible ferrofluids attracted huge interest and produced a considerable increase of the applicative potential in nanomedicine, biotechnology and environmental protection. This paper offers a brief overview of the most relevant early results and a comprehensive description of recent achievements in ferrofluid synthesis, advanced characterization, as well as the governing equations of ferrohydrodynamics, the most important interfacial phenomena and the flow properties. Finally, it provides an overview of recent advances in tunable and adaptive multifunctional materials derived from ferrofluids and a detailed presentation of the recent progress of applications in the field of sensors and actuators, ferrofluid-driven assembly and manipulation, droplet technology, including droplet generation and control, mechanical actuation, liquid computing and robotics.
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Affiliation(s)
- V Socoliuc
- Romanian Academy - Timisoara Branch, Center for Fundamental and Advanced Technical Research, Laboratory of Magnetic Fluids, Mihai Viteazu Ave. 24, 300223 Timisoara, Romania.
| | - M V Avdeev
- Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie Str. 6, 141980 Dubna, Moscow Reg., Russia.
| | - V Kuncser
- National Institute of Materials Physics, Bucharest-Magurele, 077125, Romania
| | - Rodica Turcu
- National Institute for Research and Development of Isotopic and Molecular Technologies (INCDTIM), Donat Str. 67-103, 400293 Cluj-Napoca, Romania
| | - Etelka Tombácz
- University of Szeged, Faculty of Engineering, Department of Food Engineering, Moszkvai krt. 5-7, H-6725 Szeged, Hungary.
- University of Pannonia - Soós Ernő Water Technology Research and Development Center, H-8800 Zrínyi M. str. 18, Nagykanizsa, Hungary
| | - L Vékás
- Romanian Academy - Timisoara Branch, Center for Fundamental and Advanced Technical Research, Laboratory of Magnetic Fluids, Mihai Viteazu Ave. 24, 300223 Timisoara, Romania.
- Politehnica University of Timisoara, Research Center for Complex Fluids Systems Engineering, Mihai Viteazul Ave. 1, 300222 Timisoara, Romania
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3
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Deb R, Sarma B, Dalal A. Magnetowetting dynamics of sessile ferrofluid droplets: a review. SOFT MATTER 2022; 18:2287-2324. [PMID: 35244655 DOI: 10.1039/d1sm01569a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The fascinating behavior of ferrofluids in a magnetic field has been intriguing researchers for many years. With the advancement in digital microfluidics, ferrofluid droplets have been extensively used in different applications ranging from biomedical to mechanical systems. Notably, the magnetic field can change the wetting dynamics of sessile ferrofluid droplets, leading to a plethora of interesting hydrodynamic phenomena. In the recent past, the spatiotemporal evolution of the droplet shape and contact line dynamics of a ferrofluid droplet in different magnetowetting scenarios has been explored widely. The relevant studies elucidate several critical aspects, such as the role of magnetic nanoparticles, carrier fluid, and the interaction of the magnetic fluid with the solid surface, among many others. Hence a systematic review of the progress made in understanding the fundamental and practical aspects of magnetowetting in the past decade (2010-2020) would be a helpful resource to the scientific community in the near future. Drawn by this motivation, an honest effort has been made in this Review to highlight the significant scientific findings concerning the sessile droplet magnetowetting phenomena within the timeline of interest. Several cutting-edge applications developed from the scientific findings in the purview of magnetowetting have also been discussed before outlining the conclusions and future areas of scope.
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Affiliation(s)
- Rupresha Deb
- Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Assam 781 039, India.
| | - Bhaskarjyoti Sarma
- Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Assam 781 039, India.
| | - Amaresh Dalal
- Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Assam 781 039, India.
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4
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Honecker D, Bersweiler M, Erokhin S, Berkov D, Chesnel K, Venero DA, Qdemat A, Disch S, Jochum JK, Michels A, Bender P. Using small-angle scattering to guide functional magnetic nanoparticle design. NANOSCALE ADVANCES 2022; 4:1026-1059. [PMID: 36131777 PMCID: PMC9417585 DOI: 10.1039/d1na00482d] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 01/15/2022] [Indexed: 05/14/2023]
Abstract
Magnetic nanoparticles offer unique potential for various technological, biomedical, or environmental applications thanks to the size-, shape- and material-dependent tunability of their magnetic properties. To optimize particles for a specific application, it is crucial to interrelate their performance with their structural and magnetic properties. This review presents the advantages of small-angle X-ray and neutron scattering techniques for achieving a detailed multiscale characterization of magnetic nanoparticles and their ensembles in a mesoscopic size range from 1 to a few hundred nanometers with nanometer resolution. Both X-rays and neutrons allow the ensemble-averaged determination of structural properties, such as particle morphology or particle arrangement in multilayers and 3D assemblies. Additionally, the magnetic scattering contributions enable retrieving the internal magnetization profile of the nanoparticles as well as the inter-particle moment correlations caused by interactions within dense assemblies. Most measurements are used to determine the time-averaged ensemble properties, in addition advanced small-angle scattering techniques exist that allow accessing particle and spin dynamics on various timescales. In this review, we focus on conventional small-angle X-ray and neutron scattering (SAXS and SANS), X-ray and neutron reflectometry, gracing-incidence SAXS and SANS, X-ray resonant magnetic scattering, and neutron spin-echo spectroscopy techniques. For each technique, we provide a general overview, present the latest scientific results, and discuss its strengths as well as sample requirements. Finally, we give our perspectives on how future small-angle scattering experiments, especially in combination with micromagnetic simulations, could help to optimize the performance of magnetic nanoparticles for specific applications.
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Affiliation(s)
- Dirk Honecker
- ISIS Neutron and Muon Facility, Rutherford Appleton Laboratory Didcot OX11 0QX UK
| | - Mathias Bersweiler
- Department of Physics and Materials Science, University of Luxembourg 162A Avenue de La Faïencerie L-1511 Luxembourg Grand Duchy of Luxembourg
| | - Sergey Erokhin
- General Numerics Research Lab Moritz-von-Rohr-Straße 1A D-07745 Jena Germany
| | - Dmitry Berkov
- General Numerics Research Lab Moritz-von-Rohr-Straße 1A D-07745 Jena Germany
| | - Karine Chesnel
- Brigham Young University, Department of Physics and Astronomy Provo Utah 84602 USA
| | - Diego Alba Venero
- ISIS Neutron and Muon Facility, Rutherford Appleton Laboratory Didcot OX11 0QX UK
| | - Asma Qdemat
- Universität zu Köln, Department für Chemie Luxemburger Straße 116 D-50939 Köln Germany
| | - Sabrina Disch
- Universität zu Köln, Department für Chemie Luxemburger Straße 116 D-50939 Köln Germany
| | - Johanna K Jochum
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München Lichtenbergstraße 1 85748 Garching Germany
| | - Andreas Michels
- Department of Physics and Materials Science, University of Luxembourg 162A Avenue de La Faïencerie L-1511 Luxembourg Grand Duchy of Luxembourg
| | - Philipp Bender
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München Lichtenbergstraße 1 85748 Garching Germany
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5
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Saini A, Theis-Bröhl K, Koutsioubas A, Krycka KL, Borchers JA, Wolff M. Magnetic Particle Self-Assembly at Functionalized Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:4064-4071. [PMID: 33797254 PMCID: PMC8154863 DOI: 10.1021/acs.langmuir.0c03235] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We study the assembly of magnetite nanoparticles in water-based ferrofluids in wetting layers close to silicon substrates with different functionalization without and with an out-of-plane magnetic field. For particles of nominal sizes 5, 15, and 25 nm, we extract density profiles from neutron reflectivity measurements. We show that self-assembly is only promoted by a magnetic field if a seed layer is formed at the silicon substrate. Such a layer can be formed by chemisorption of activated N-hydroxysuccinimide ester-coated nanoparticles at a (3-aminopropyl)triethoxysilane functionalized surface. Less dense packing is reported for physisorption of the same particles at a piranha-treated (strongly hydrophilic) silicon wafer, and no wetting layer is found for a self-assembled monolayer of octadecyltrichlorosilane (strongly hydrophobic) at the interface. We show that once the seed layer is formed and under an out-of-plane magnetic field further wetting layers assemble. These layers become denser with time, larger magnetic fields, higher particle concentrations, and larger moment of the nanoparticles.
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Affiliation(s)
- Apurve Saini
- Department
for Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | | | - Alexandros Koutsioubas
- Jülich
Centre for Neutron Science JCNS at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich GmbH, Lichtenbergstraßze 1, 85748 Garching, Germany
| | - Kathryn L. Krycka
- NIST
Center for Neutron Research, Gaithersburg, Maryland 20899-6102, United States
| | - Julie A. Borchers
- NIST
Center for Neutron Research, Gaithersburg, Maryland 20899-6102, United States
| | - Max Wolff
- Department
for Physics and Astronomy, Uppsala University, Uppsala, Sweden
- . Phone: + 46 (0)18−471
3590. Fax: + 46
(0)18−471 3524
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6
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Theis-Bröhl K, Saini A, Wolff M, Dura JA, Maranville BB, Borchers JA. Self-Assembly of Magnetic Nanoparticles in Ferrofluids on Different Templates Investigated by Neutron Reflectometry. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E1231. [PMID: 32599954 PMCID: PMC7353075 DOI: 10.3390/nano10061231] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 01/24/2023]
Abstract
In this article we review the process by which magnetite nanoparticles self-assemble onto solid surfaces. The focus is on neutron reflectometry studies providing information on the density and magnetization depth profiles of buried interfaces. Specific attention is given to the near-interface "wetting" layer and to examples of magnetite nanoparticles on a hydrophilic silicon crystal, one coated with (3-Aminopropyl)triethoxysilane, and finally, one with a magnetic film with out-of-plane magnetization.
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Affiliation(s)
- Katharina Theis-Bröhl
- University of Applied Sciences Bremerhaven, An der Karlstadt 8, 27568 Bremerhaven, Germany
| | - Apurve Saini
- Department for Physics and Astronomy, Uppsala University, Lägerhyddsvägen 1, 752 37 Uppsala, Sweden; (A.S.); (M.W.)
| | - Max Wolff
- Department for Physics and Astronomy, Uppsala University, Lägerhyddsvägen 1, 752 37 Uppsala, Sweden; (A.S.); (M.W.)
| | - Joseph A. Dura
- NIST Center for Neutron Research, 100 Bureau Drive, Gaithersburg, MD 20899-6102, USA; (J.A.D.); (B.B.M.); (J.A.B.)
| | - Brian B. Maranville
- NIST Center for Neutron Research, 100 Bureau Drive, Gaithersburg, MD 20899-6102, USA; (J.A.D.); (B.B.M.); (J.A.B.)
| | - Julie A. Borchers
- NIST Center for Neutron Research, 100 Bureau Drive, Gaithersburg, MD 20899-6102, USA; (J.A.D.); (B.B.M.); (J.A.B.)
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7
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Abstract
Iron oxide nanoparticles are the basic components of the most promising magneto-responsive systems for nanomedicine, ranging from drug delivery and imaging to hyperthermia cancer treatment, as well as to rapid point-of-care diagnostic systems with magnetic nanoparticles. Advanced synthesis procedures of single- and multi-core iron-oxide nanoparticles with high magnetic moment and well-defined size and shape, being designed to simultaneously fulfill multiple biomedical functionalities, have been thoroughly evaluated. The review summarizes recent results in manufacturing novel magnetic nanoparticle systems, as well as the use of proper characterization methods that are relevant to the magneto-responsive nature, size range, surface chemistry, structuring behavior, and exploitation conditions of magnetic nanosystems. These refer to particle size, size distribution and aggregation characteristics, zeta potential/surface charge, surface coating, functionalization and catalytic activity, morphology (shape, surface area, surface topology, crystallinity), solubility and stability (e.g., solubility in biological fluids, stability on storage), as well as to DC and AC magnetic properties, particle agglomerates formation, and flow behavior under applied magnetic field (magnetorheology).
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8
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Salez TJ, Kouyaté M, Filomeno C, Bonetti M, Roger M, Demouchy G, Dubois E, Perzynski R, Cēbers A, Nakamae S. Magnetically enhancing the Seebeck coefficient in ferrofluids. NANOSCALE ADVANCES 2019; 1:2979-2989. [PMID: 36133602 PMCID: PMC9419873 DOI: 10.1039/c9na00109c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/03/2019] [Indexed: 05/22/2023]
Abstract
The influence of the magnetic field on the Seebeck coefficient (Se) was investigated in dilute magnetic nanofluids (ferrofluids) composed of maghemite magnetic nanoparticles dispersed in dimethyl-sulfoxide (DMSO). A 25% increase in the Se value was found when the external magnetic field was applied perpendicularly to the temperature gradient, reminiscent of an increase in the Soret coefficient (S T, concentration gradient) observed in the same fluids. In-depth analysis of experimental data, however, revealed that different mechanisms are responsible for the observed magneto-thermoelectric and -thermodiffusive phenomena. Possible physical and physico-chemical origins leading to the enhancement of the fluids' Seebeck coefficient are discussed.
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Affiliation(s)
- Thomas J Salez
- Service de physique de l'état condensé, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette Cedex France +33 1 6908 8786 +33 1 6908 7538
- École des Ponts ParisTech 6 et 8 avenue Blaise Pascal, Champs-sur-Marne F-77455 Marne-la-Vallée France
| | - Mansour Kouyaté
- Physico-chimie des Electrolytes et Nanosystémes InterfaciauX, Sorbonne Université, CNRS F-75005 Paris France
| | - Cleber Filomeno
- Physico-chimie des Electrolytes et Nanosystémes InterfaciauX, Sorbonne Université, CNRS F-75005 Paris France
- Inst. de Quémica, Complex Fluid Group, Universidade de Brasília Brasília Brazil
| | - Marco Bonetti
- Service de physique de l'état condensé, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette Cedex France +33 1 6908 8786 +33 1 6908 7538
| | - Michel Roger
- Service de physique de l'état condensé, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette Cedex France +33 1 6908 8786 +33 1 6908 7538
| | - Gilles Demouchy
- Physico-chimie des Electrolytes et Nanosystémes InterfaciauX, Sorbonne Université, CNRS F-75005 Paris France
- Département de Physique, Université de Cergy Pontoise 33 Boulevard du Port 95011 Cergy-Pontoise Cedex France
| | - Emmanuelle Dubois
- Physico-chimie des Electrolytes et Nanosystémes InterfaciauX, Sorbonne Université, CNRS F-75005 Paris France
| | - Régine Perzynski
- Physico-chimie des Electrolytes et Nanosystémes InterfaciauX, Sorbonne Université, CNRS F-75005 Paris France
| | - Andrejs Cēbers
- MMML Lab, Faculty of Physics and Mathematics, University of Latvia Zellu-8 LV-1002 Riga Latvia
| | - Sawako Nakamae
- Service de physique de l'état condensé, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette Cedex France +33 1 6908 8786 +33 1 6908 7538
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9
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Avdeev MV, Bodnarchuk VI, Petrenko VI, Gapon IV, Tomchuk OV, Nagorny AV, Ulyanov VA, Bulavin LA, Aksenov VL. Neutron time-of-flight reflectometer GRAINS with horizontal sample plane at the IBR-2 reactor: Possibilities and prospects. CRYSTALLOGR REP+ 2017. [DOI: 10.1134/s1063774517060025] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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10
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Vorobiev A, Khassanov A, Ukleev V, Snigireva I, Konovalov O. Substantial Difference in Ordering of 10, 15, and 20 nm Iron Oxide Nanoparticles on a Water Surface: In Situ Characterization by the Grazing Incidence X-ray Scattering. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:11639-11648. [PMID: 26399881 DOI: 10.1021/acs.langmuir.5b02644] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In the present study, for the first time, a unique combination of in situ grazing incidence small-angle X-ray scattering and X-ray reflectivity, accompanied by the pressure-area isotherm analysis, Brewster angle microscopy, and ex situ scanning electron microscopy, was applied for investigation of two-dimensional superlattices of magnetic nanoparticles as they form on a water surface in a Langmuir trough. Iron oxide particles of different sizes stabilized with a single layer of oleic acid were used. It is demonstrated that monodisperse 10 nm particles on a water surface reproducibly form identical highly ordered monolayers in a wide range of experimental conditions, while monodisperse 20 nm particles always form compact three-dimensional clusters and never the monolayers. Monodisperse particles of an intermediate size, 15 nm in diameter, build a metastable monolayer, which shows a tendency for spontaneous transformation to bi-, tri-, and multilayer islands. The importance to use both grazing incidence small-angle X-ray scattering and X-ray reflectivity together with the complementary techniques, to avoid misinterpretation of separate experimental data sets, is underlined.
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Affiliation(s)
- A Vorobiev
- Department of Physics and Astronomy, Uppsala University , Box 516, 751 20 Uppsala, Sweden
- European Synchrotron Radiation Facility , 71 Avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France
| | - A Khassanov
- European Synchrotron Radiation Facility , 71 Avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France
- Organic Materials and Devices, Friedrich-Alexander-Universität Erlangen-Nürnberg , Martensstraße 7, 91058 Erlangen, Germany
| | - V Ukleev
- Department of Physics and Astronomy, Uppsala University , Box 516, 751 20 Uppsala, Sweden
- Petersburg Nuclear Physics Institute , Orlova Roscha, Gatchina, St. Petersburg 188300, Russia
| | - I Snigireva
- European Synchrotron Radiation Facility , 71 Avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France
| | - O Konovalov
- European Synchrotron Radiation Facility , 71 Avenue des Martyrs, CS 40220, 38043 Grenoble Cedex 9, France
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11
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Petrenko V, Avdeev M, Garamus V, Bulavin L, Kopcansky P. Impact of polyethylene glycol on aqueous micellar solutions of sodium oleate studied by small-angle neutron scattering. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2014.11.064] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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12
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Theis-Bröhl K, Gutfreund P, Vorobiev A, Wolff M, Toperverg BP, Dura JA, Borchers JA. Self assembly of magnetic nanoparticles at silicon surfaces. SOFT MATTER 2015; 11:4695-704. [PMID: 25971712 DOI: 10.1039/c5sm00484e] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Neutron reflectometry was used to study the assembly of magnetite nanoparticles in a water-based ferrofluid close to a silicon surface. Under three conditions, static, under shear and with a magnetic field, the depth profile is extracted. The particles have an average diameter of 11 nm and a volume density of 5% in a D2O-H2O mixture. They are surrounded by a 4 nm thick bilayer of carboxylic acid for steric repulsion. The reflectivity data were fitted to a model using a least square routine based on the Parratt formalism. From the scattering length density depth profiles the following behavior is concluded: the fits indicate that excess carboxylic acid covers the silicon surface and almost eliminates the water in the densely packed wetting layer that forms close to the silicon surface. Under constant shear the wetting layer persists but a depletion layer forms between the wetting layer and the moving ferrofluid. Once the flow is stopped, the wetting layer becomes more pronounced with dense packing and is accompanied by a looser packed second layer. In the case of an applied magnetic field the prolate particles experience a torque and align with their long axes along the silicon surface which leads to a higher particle density.
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Affiliation(s)
- Katharina Theis-Bröhl
- University of Applied Sciences Bremerhaven, An der Karlstadt 8, 27568 Bremerhaven, Germany.
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13
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Affiliation(s)
- Robert Hayes
- Discipline
of Chemistry, The University of Newcastle, NSW 2308, Callaghan, Australia
| | - Gregory G. Warr
- School
of Chemistry, The University of Sydney, NSW 2006, Sydney, Australia
| | - Rob Atkin
- Discipline
of Chemistry, The University of Newcastle, NSW 2308, Callaghan, Australia
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14
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Richardi J, Weis JJ. Low density mesostructures of confined dipolar particles in an external field. J Chem Phys 2011; 135:124502. [DOI: 10.1063/1.3638048] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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15
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Avdeev MV, Bodnarchuk VI, Lauter-Pasyuk VV, Lauter H, Aksenov VL, Yaradaikin SP, Ulyanov VA, Trounov VA, Kalinin SI. Project of the new multifunctional reflectometer GRAINS with horizontal sample plane at the IBR-2M pulsed reactor in Dubna. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/251/1/012060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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16
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Jordanovic J, Klapp SH. Field-induced layering of confined ferromagnetic nanoparticles: the role of attractive interactions. Mol Phys 2010. [DOI: 10.1080/00268970902889634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Avdeev MV, Feoktystov AV, Kopcansky P, Lancz G, Garamus VM, Willumeit R, Timko M, Koneracka M, Zavisova V, Tomasovicova N, Jurikova A, Csach K, Bulavin LA. Structure of water-based ferrofluids with sodium oleate and polyethylene glycol stabilization by small-angle neutron scattering: contrast-variation experiments. J Appl Crystallogr 2010. [DOI: 10.1107/s0021889810025379] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Contrast variation in small-angle neutron scattering (SANS) experiments is used to compare the structures of a water-based ferrofluid, where magnetite nanoparticles are stabilized by sodium oleate, and its mixture with biocompatible polyethylene glycol, PEG. The basic functions approach is applied, which takes into account the effects of polydispersity and magnetic scattering. Different types of stable aggregates of colloidal particles are revealed in both fluids. The addition of PEG results in a reorganization of the structure of the aggregates: the initial comparatively small and compact aggregates (about 40 nm in size) are replaced by large (more than 120 nm in size) fractal-type structures. It is postulated that these large structures are composed of single magnetite particles coated with PEG, which replaces sodium oleate. Micelle formation involving free sodium oleate is observed in both fluids. The structures of the fluids remain unchanged with increasing temperature up to 343 K. New and specific possibilities of SANS contrast variation with respect to multicomponent systems with different aggregates are considered.
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18
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Richardi J, Pileni MP, Weis JJ. Self-organization of confined dipolar particles in a parallel field. J Chem Phys 2009; 130:124515. [DOI: 10.1063/1.3100304] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Szalai I, Dietrich S. Phase transitions and ordering of confined dipolar fluids. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2009; 28:347-359. [PMID: 19229569 DOI: 10.1140/epje/i2008-10424-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 01/13/2009] [Indexed: 05/27/2023]
Abstract
We apply a modified mean-field density functional theory to determine the phase behavior of Stockmayer fluids in slit-like pores formed by two walls with identical substrate potentials. Based on the Carnahan-Starling equation of state, a fundamental-measure theory is employed to incorporate the effects of short-ranged hard-sphere-like correlations while the long-ranged contributions to the fluid interaction potential are treated perturbatively. The liquid-vapor, ferromagnetic-liquid-vapor, and ferromagnetic-liquid-isotropic-liquid first-order phase separations are investigated. The local orientational structure of the anisotropic and inhomogeneous ferromagnetic liquid phase is also studied. We discuss how the phase diagrams are shifted and distorted upon varying the pore width.
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Affiliation(s)
- I Szalai
- Institute of Physics, University of Pannonia, Hungary.
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20
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Vorobiev A, Gordeev G, Konovalov O, Orlova D. Surface structure of sterically stabilized ferrofluids in a normal magnetic field: grazing-incidence x-ray study. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:031403. [PMID: 19391940 DOI: 10.1103/physreve.79.031403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Revised: 01/07/2009] [Indexed: 05/27/2023]
Abstract
We studied the internal structure of sterically stabilized water- and oil-based ferrofluids in the vicinity of the free interface with a gas by means of x-ray reflectometry and grazing-incidence x-ray diffraction. It was found that in-depth distribution of the magnetic nanoparticles in the layer close to the interface is essentially inhomogeneous. In the case of water-based ferrofluids an enhanced concentration of surfactant and subsequent reduced concentration of the particles were detected in the 100-200-A -thick interface-adjacent layer. Scattering patterns possessing characteristic features of powder diffraction revealed partial ordering of the surfactant in a multilamellar structure. External magnetic fields applied perpendicular to the interface effectively reduced thickness of the depleted layer bringing the particles from the bulk to the surface. However no field-induced correlations between the particles were detected. In the top 500-A -thick layer of an oil-based ferrofluid depletion of the particles density was also present; however, no special arrangement of the surfactant molecules was manifested by the experimental data. Interestingly, for all samples we observed wavy surface deformation appearing in the normal magnetic field of a strength H much smaller than the critical values H_{c} calculated according to the conventional theory of ferrofluid surface instability. This deformation with lateral periodicity of a few millimeters has an amplitude smoothly increasing up to a few microns at H=0.5H_{c} .
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Affiliation(s)
- A Vorobiev
- European Synchrotron Radiation Facility, 6 rue Jules Horowitz BP 220, 38043 Grenoble Cedex, France
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Jordanovic J, Klapp SHL. Structure of ferrofluid nanofilms in homogeneous magnetic fields. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:021405. [PMID: 19391745 DOI: 10.1103/physreve.79.021405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Indexed: 05/27/2023]
Abstract
We report molecular dynamics simulations results for model ferrofluid films subject to an external, homogeneous magnetic field directed parallel or perpendicular to the film surfaces. The interactions between the magnetic nanoparticles are modeled via the Stockmayer potential. In a previous study [J. Jordanovic and S. H. L. Klapp, Phys. Rev. Lett. 101, 038302 (2008)] we have shown that an external field can control the number and internal structure of the layers characterizing the fluid films, in qualitative agreement with experiments. Here we explore the dependence of the layering effects on thermodynamic conditions, and we analyze the results from an energetic (microscopic and macroscopic) perspective. As a special case we investigate a monolayer to bilayer transition induced via a perpendicular field.
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Affiliation(s)
- Jelena Jordanovic
- Institut für Theoretische Physik, Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
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Kooij ES, Gâlcă AC, Poelsema B. Field induced phase segregation in ferrofluids. J Colloid Interface Sci 2008; 327:261-5. [PMID: 18774140 DOI: 10.1016/j.jcis.2008.08.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Revised: 08/11/2008] [Accepted: 08/14/2008] [Indexed: 11/29/2022]
Abstract
We study the phase segregation in magnetite ferrofluids under the influence of an external magnetic field. A phase with lower nanoparticle density and corresponding higher optical transmission is formed in the bottom of a glass cell in the presence of only a very modest magnetic field gradient (smaller than 25 T/m). The flux density in our magnetic configuration is simulated using finite element methods. Upon switching off the external magnetic field, the low-density phase develops into a 'bubble'-like feature. The kinetics of this 'bubble' in the absence and presence of a magnetic field are described and analyzed in terms of a simple model, which takes into account buoyancy and drag forces.
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Affiliation(s)
- E S Kooij
- Solid State Physics group, MESA(+) Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands.
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Trasca RA, Klapp SHL. Structure formation in layered ferrofluid nanofilms. J Chem Phys 2008; 129:084702. [DOI: 10.1063/1.2971182] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Jordanovic J, Klapp SHL. Field-induced layer formation in dipolar nanofilms. PHYSICAL REVIEW LETTERS 2008; 101:038302. [PMID: 18764302 DOI: 10.1103/physrevlett.101.038302] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2008] [Indexed: 05/26/2023]
Abstract
Using molecular dynamics simulations, we demonstrate that the layering of confined colloidal particles with dipolar interactions, such as ferrofluids, in slablike geometries can be controlled by homogeneous external fields. For suitable surface separations, strong fields directed perpendicular to the film plane do not only align the particles but create additional layers in the system. The reverse effect occurs with an in-plane field which can induce a collapse of layers. Both effects are accompanied by pronounced particle rearrangements in lateral directions. Our simulation results are consistent with recent experiments of ferrofluids at surfaces.
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Affiliation(s)
- Jelena Jordanovic
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin, Sekr. C7, Strasse des 17. Juni 115, D-10623 Berlin, Germany
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Shen M, Cao J, Xue H, Huang J, Zhou L. Structure of polydisperse electrorheological fluids: Experiment and theory. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.03.066] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Tartaj P, Morales MP, Veintemillas-Verdaguer S, Gonzalez-Carreño T, Serna CJ. chapter 5 Synthesis, Properties and Biomedical Applications of Magnetic Nanoparticles. HANDBOOK OF MAGNETIC MATERIALS 2006. [DOI: 10.1016/s1567-2719(05)16005-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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