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Petrov SA, Dudina DV, Ukhina AV, Bokhonov BB. Morphological and Structural Transformations of Fe-Pd Powder Alloys Formed by Galvanic Replacement, Annealing and Acid Treatment. Materials (Basel) 2022; 15:ma15103571. [PMID: 35629598 PMCID: PMC9145926 DOI: 10.3390/ma15103571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 05/12/2022] [Accepted: 05/15/2022] [Indexed: 02/04/2023]
Abstract
In this article, we report the preparation and structural features of Fe-Pd powder alloys formed by galvanic replacement, annealing and selective dissolution of iron via acid treatment. The alloys were studied by the X-ray diffraction phase analysis, Mössbauer spectroscopy, scanning electron microscopy, and energy-dispersive spectroscopy. The Fe@Pd core–shell particles were obtained by a galvanic replacement reaction occurring upon treatment of a body-centered cubic (bcc) iron powder by a solution containing PdCl42− ions. It was found that the shells are a face-centered cubic (fcc) Pd(Fe) solid solution. HCl acid treatment of the Fe@Pd core–shell particles resulted in the formation of hollow Pd-based particles, as the bcc phase was selectively dissolved from the cores. Annealing of the Fe@Pd core–shell particles at 800 °C led to the formation of fcc Fe-Pd solid solution. Acid treatment of the Fe-Pd alloys formed by annealing of the core–shell particles allowed selectively dissolving iron from the bcc Fe-based phase (Fe(Pd) solid solution), while the fcc Fe-rich Fe-Pd solid solution remained stable (resistant to acid corrosion). It was demonstrated that the phase composition and the Fe/Pd ratio in the alloys (phases) can be tailored by applying annealing and/or acid treatment to the as-synthesized Fe@Pd core–shell particles.
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Affiliation(s)
- Sergey A Petrov
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, Kutateladze Str. 18, 630128 Novosibirsk, Russia
| | - Dina V Dudina
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, Kutateladze Str. 18, 630128 Novosibirsk, Russia
| | - Arina V Ukhina
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, Kutateladze Str. 18, 630128 Novosibirsk, Russia
| | - Boris B Bokhonov
- Institute of Solid State Chemistry and Mechanochemistry SB RAS, Kutateladze Str. 18, 630128 Novosibirsk, Russia
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Dolmatov AV, Maklakov SS, Zezyulina PA, Osipov AV, Petrov DA, Naboko AS, Polozov VI, Maklakov SA, Starostenko SN, Lagarkov AN. Deposition of a SiO 2 Shell of Variable Thickness and Chemical Composition to Carbonyl Iron: Synthesis and Microwave Measurements. Sensors (Basel) 2021; 21:4624. [PMID: 34300364 PMCID: PMC8309671 DOI: 10.3390/s21144624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 11/17/2022]
Abstract
Protective SiO2 coating deposited to iron microparticles is highly demanded both for the chemical and magnetic performance of the latter. Hydrolysis of tetraethoxysilane is the crucial method for SiO2 deposition from a solution. The capabilities of this technique have not been thoroughly studied yet. Here, two factors were tested to affect the chemical composition and the thickness of the SiO2 shell. It was found that an increase in the hydrolysis reaction time thickened the SiO2 shell from 100 to 200 nm. Moreover, a decrease in the acidity of the reaction mixture not only thickened the shell but also varied the chemical composition from SiO3.0 to SiO8.6. The thickness and composition of the dielectric layer were studied by scanning electron microscopy and energy-dispersive X-ray analysis. Microwave permeability and permittivity of the SiO2-coated iron particles mixed with a paraffin wax matrix were measured by the coaxial line technique. An increase in thickness of the silica layer decreased the real quasi-static permittivity. The changes observed were shown to agree with the Maxwell Garnett effective medium theory. The new method developed to fine-tune the chemical properties of the protective SiO2 shell may be helpful for new magnetic biosensor designs as it allows for biocompatibility adjustment.
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Affiliation(s)
- Arthur V. Dolmatov
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
- Moscow Institute of Physics and Technology, National Research University, 9 Institutskiy per., 141700 Dolgoprudny, Russia
| | - Sergey S. Maklakov
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
| | - Polina A. Zezyulina
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
| | - Alexey V. Osipov
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
| | - Dmitry A. Petrov
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
| | - Andrey S. Naboko
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
| | - Viktor I. Polozov
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
- Moscow Institute of Physics and Technology, National Research University, 9 Institutskiy per., 141700 Dolgoprudny, Russia
| | - Sergey A. Maklakov
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
| | - Sergey N. Starostenko
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
| | - Andrey N. Lagarkov
- Institute for Theoretical and Applied Electromagnetics RAS, Izhorskaya St. 13, 125412 Moscow, Russia; (A.V.D.); (P.A.Z.); (A.V.O.); (D.A.P.); (A.S.N.); (V.I.P.); (S.A.M.); (S.N.S.); (A.N.L.)
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De Marco ML, Jiang T, Fang J, Lacomme S, Zheng Y, Baron A, Korgel BA, Barois P, Drisko GL, Aymonier C. Broadband Forward Light Scattering by Architectural Design of Core-Shell Silicon Particles. Adv Funct Mater 2021; 31:2100915. [PMID: 38031546 PMCID: PMC10686547 DOI: 10.1002/adfm.202100915] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Indexed: 12/01/2023]
Abstract
A goal in the field of nanoscale optics is the fabrication of nanostructures with strong directional light scattering at visible frequencies. Here, the synthesis of Mie-resonant core-shell particles with overlapping electric and magnetic dipole resonances in the visible spectrum is demonstrated. The core consists of silicon surrounded by a lower index silicon oxynitride (SiOxNy) shell of an adjustable thickness. Optical spectroscopies coupled to Mie theory calculations give the first experimental evidence that the relative position and intensity of the magnetic and electric dipole resonances are tuned by changing the core-shell architecture. Specifically, coating a high-index particle with a low-index shell coalesces the dipoles, while maintaining a high scattering efficiency, thus generating broadband forward scattering. This synthetic strategy opens a route toward metamaterial fabrication with unprecedented control over visible light manipulation.
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Affiliation(s)
| | - Taizhi Jiang
- McKetta Department of Chemical Engineering, 200 E Dean Keeton St, The University of Texas at Austin, Austin TX 78712, USA
| | - Jie Fang
- Walker Department of Mechanical Engineering and Texas Materials Institute, 204 E Dean Keeton St, The University of Texas at Austin, Austin TX 78712, USA
| | - Sabrina Lacomme
- Univ. Bordeaux, CNRS, INSERM, Bordeaux Imaging Center, BIC, UMS 3420, US 4, Bordeaux F-33000, France
| | - Yuebing Zheng
- Walker Department of Mechanical Engineering and Texas Materials Institute, 204 E Dean Keeton St, The University of Texas at Austin, Austin TX 78712, USA
| | - Alexandre Baron
- CNRS, Univ. Bordeaux, CRPP, UMR 5031, Pessac F-33600, France
| | - Brian A Korgel
- McKetta Department of Chemical Engineering, 200 E Dean Keeton St, The University of Texas at Austin, Austin TX 78712, USA
| | - Philippe Barois
- CNRS, Univ. Bordeaux, CRPP, UMR 5031, Pessac F-33600, France
| | - Glenna L Drisko
- CNRS, Univ. Bordeaux, Bordeaux INP, ICMCB, UMR 5026, Pessac F-33600, France
| | - Cyril Aymonier
- CNRS, Univ. Bordeaux, Bordeaux INP, ICMCB, UMR 5026, Pessac F-33600, France
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Suzuki S, Lee S, Miyajima T, Kato K, Sugawara-Narutaki A, Sakurai M, Nagata F. Evaluation of Drug-Loading Ability of Poly(Lactic Acid)/Hydroxyapatite Core-Shell Particles. Materials (Basel) 2021; 14:1959. [PMID: 33919727 PMCID: PMC8070725 DOI: 10.3390/ma14081959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/01/2021] [Accepted: 04/12/2021] [Indexed: 12/12/2022]
Abstract
Poly(lactic acid)/hydroxyapatite (PLA/HAp) core-shell particles are prepared using the emulsification method. These particles are safe for living organisms because they are composed of biodegradable polymers and biocompatible ceramics. These particles are approximately 50-100 nm in size, and their hydrophobic substance loading can be controlled. Hence, PLA/HAp core-shell particles are expected to be used as drug delivery carriers for hydrophobic drugs. In this work, PLA/HAp core-shell particles with a loading of vitamin K1 were prepared, and their drug-loading ability was evaluated. The particles were 40-80 nm in diameter with a PLA core and a HAp shell. The particle size increased with an increase in the vitamin K1 loading. The drug-loading capacity (LC) value of the particles, an indicator of their drug-loading ability, was approximately 250%, which is higher than the previously reported values. The amount of vitamin K1 released from the particles increased as the pH of the soaking solution decreased because the HAp shell easily dissolved under the acidic conditions. The PLA/HAp particles prepared in this work were found to be promising candidates for drug delivery carriers because of their excellent drug-loading ability and pH sensitivity.
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Affiliation(s)
- Seiya Suzuki
- National Institute of Advanced Industrial Science and Technology (AIST), 2266-98 Anagahora, Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan; (S.S.); (T.M.); (K.K.)
- Department of Applied Chemistry, College of Engineering, Chubu University, Matsumoto-cho, Kasugai 487-8501, Japan;
| | - Sungho Lee
- National Institute of Advanced Industrial Science and Technology (AIST), 2266-98 Anagahora, Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan; (S.S.); (T.M.); (K.K.)
| | - Tatsuya Miyajima
- National Institute of Advanced Industrial Science and Technology (AIST), 2266-98 Anagahora, Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan; (S.S.); (T.M.); (K.K.)
| | - Katsuya Kato
- National Institute of Advanced Industrial Science and Technology (AIST), 2266-98 Anagahora, Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan; (S.S.); (T.M.); (K.K.)
| | - Ayae Sugawara-Narutaki
- Department of Energy Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan;
| | - Makoto Sakurai
- Department of Applied Chemistry, College of Engineering, Chubu University, Matsumoto-cho, Kasugai 487-8501, Japan;
| | - Fukue Nagata
- National Institute of Advanced Industrial Science and Technology (AIST), 2266-98 Anagahora, Shimoshidami, Moriyama-ku, Nagoya 463-8560, Japan; (S.S.); (T.M.); (K.K.)
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Abstract
Chromatographic separation has been widely applied in various fields, such as chemical engineering, precision medicine, energy, and biology. Because chromatographic separation is based on differential partitioning between the mobile phase and stationary phase and affected by band dispersion and mass transfer resistance from these two phases, the materials used as the stationary phase play a decisive role in separation performance. In this review, we discuss the design of separation materials to achieve the separation with high efficiency and high resolution and highlight the well-defined materials with uniform pore structure and unique properties. The achievements, recent developments, challenges, and future trends of such materials are discussed. Furthermore, the surface functionalization of separation ma-terials for further improvement of separation performance is reviewed. Finally, future research directions and the challenges of chromatographic separation are presented.
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Affiliation(s)
- Yu Liang
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China;
| | - Lihua Zhang
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China;
| | - Yukui Zhang
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China;
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Ding T, Zhao Q, Smoukov SK, Baumberg JJ. Selectively Patterning Polymer Opal Films via Microimprint Lithography. Adv Opt Mater 2014; 2:1098-1104. [PMID: 26167447 PMCID: PMC4497474 DOI: 10.1002/adom.201400327] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Indexed: 05/29/2023]
Abstract
Large-scale structural color flexible coatings have been hard to create, and patterning color on them is key to many applications, including large-area strain sensors, wall-size displays, security devices, and smart fabrics. To achieve controlled tuning, a micro-imprinting technique is applied here to pattern both the surface morphology and the structural color of the polymer opal films (POFs). These POFs are made of 3D ordered arrays of hard spherical particles embedded inside soft shells. The soft outer shells cause the POFs to deform upon imprinting with a pre-patterned stamp, driving a flow of the soft polymer and a rearrangement of the hard spheres within the films. As a result, a patterned surface morphology is generated within the POFs and the structural colors are selectively modified within different regions. These changes are dependent on the pressure, temperature, and duration of imprinting, as well as the feature sizes in the stamps. Moreover, the pattern geometry and structural colors can then be further tuned by stretching. Micropattern color generation upon imprinting depends on control of colloidal transport in a polymer matrix under shear flow and brings many potential properties including stretchability and tunability, as well as being of fundamental interest.
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Affiliation(s)
- Tao Ding
- Nanophotonic Centre Cavendish Laboratory University of Cambridge CB3 0HE, UK E-mail: ; Department of Materials Science and Metallurgy 27 Charles Babbage Road University of Cambridge CB3 0FS, UK
| | - Qibin Zhao
- Nanophotonic Centre Cavendish Laboratory University of Cambridge CB3 0HE, UK E-mail:
| | - Stoyan K Smoukov
- Department of Materials Science and Metallurgy 27 Charles Babbage Road University of Cambridge CB3 0FS, UK
| | - Jeremy J Baumberg
- Nanophotonic Centre Cavendish Laboratory University of Cambridge CB3 0HE, UK E-mail:
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Moraes J, Ohno K, Gody G, Maschmeyer T, Perrier S. The synthesis of well-defined poly(vinylbenzyl chloride)-grafted nanoparticles via RAFT polymerization. Beilstein J Org Chem 2013; 9:1226-34. [PMID: 23843918 PMCID: PMC3701384 DOI: 10.3762/bjoc.9.139] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 05/28/2013] [Indexed: 11/23/2022] Open
Abstract
We describe the use of one of the most advanced radical polymerization techniques, the reversible addition fragmentation chain transfer (RAFT) process, to produce highly functional core–shell particles based on a silica core and a shell made of functional polymeric chains with very well controlled structure. The versatility of RAFT polymerization is illustrated by the control of the polymerization of vinylbenzyl chloride (VBC), a highly functional monomer, with the aim of designing silica core–poly(VBC) shell nanoparticles. Optimal conditions for the control of VBC polymerization by RAFT are first established, followed by the use of the “grafting from” method to yield polymeric brushes that form a well-defined shell surrounding the silica core. We obtain particles that are monodisperse in size, and we demonstrate that the exceptional control over their dimensions is achieved by careful tailoring the conditions of the radical polymerization.
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Affiliation(s)
- John Moraes
- Key Centre for Polymers & Colloids, School of Chemistry, The University of Sydney, NSW 2006, Australia
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Dobbrow C, Schmidt AM. Improvement of the oxidation stability of cobalt nanoparticles. Beilstein J Nanotechnol 2012; 3:75-81. [PMID: 22428099 PMCID: PMC3304312 DOI: 10.3762/bjnano.3.9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 12/09/2011] [Indexed: 05/27/2023]
Abstract
In order to enhance the resistance of cobalt nanoparticles to oxidation in air, the impact of different stabilization strategies on the isothermal oxidation of particle dispersions and powders was kinetically investigated and compared to as-prepared particle preparations. A post-synthesis treatment with different alcohols was employed, and we also investigate the influence of two different polymer shells on the oxidation process. We found a parabolic decrease of the magnetization for all particle charges, indicating that the process is dominated by a diffusion of oxygen to the cobalt core and a radial growth of the oxide layer from the particle surface to the core. A significant deceleration of the oxidation process was observed for all alcohol-passivated particle preparations, and this resulted finally in a stagnation effect. The stabilizing effect increases in the sequence Co@OA/MeOH < Co@OA/EtOH < Co@OA/iPrOH. For polymer-coated particle preparations Co@PCL and Co@PS, the deceleration was even more pronounced. The results demonstrate that cobalt nanoparticles can effectively be protected against oxidation in order to improve their mid- to longterm stability.
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Affiliation(s)
- Celin Dobbrow
- Department für Chemie, Universität zu Köln, Luxemburger Str. 116, D-50939 Köln, Germany
| | - Annette M Schmidt
- Department für Chemie, Universität zu Köln, Luxemburger Str. 116, D-50939 Köln, Germany
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Wiedwald U, Han L, Biskupek J, Kaiser U, Ziemann P. Preparation and characterization of supported magnetic nanoparticles prepared by reverse micelles. Beilstein J Nanotechnol 2010; 1:24-47. [PMID: 21977392 PMCID: PMC3045932 DOI: 10.3762/bjnano.1.5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2010] [Accepted: 11/06/2010] [Indexed: 05/07/2023]
Abstract
Monatomic (Fe, Co) and bimetallic (FePt and CoPt) nanoparticles were prepared by exploiting the self-organization of precursor loaded reverse micelles. Achievements and limitations of the preparation approach are critically discussed. We show that self-assembled metallic nanoparticles can be prepared with diameters d = 2-12 nm and interparticle distances D = 20-140 nm on various substrates. Structural, electronic and magnetic properties of the particle arrays were characterized by several techniques to give a comprehensive view of the high quality of the method. For Co nanoparticles, it is demonstrated that magnetostatic interactions can be neglected for distances which are at least 6 times larger than the particle diameter. Focus is placed on FePt alloy nanoparticles which show a huge magnetic anisotropy in the L1(0) phase, however, this is still less by a factor of 3-4 when compared to the anisotropy of the bulk counterpart. A similar observation was also found for CoPt nanoparticles (NPs). These results are related to imperfect crystal structures as revealed by HRTEM as well as to compositional distributions of the prepared particles. Interestingly, the results demonstrate that the averaged effective magnetic anisotropy of FePt nanoparticles does not strongly depend on size. Consequently, magnetization stability should scale linearly with the volume of the NPs and give rise to a critical value for stability at ambient temperature. Indeed, for diameters above 6 nm such stability is observed for the current FePt and CoPt NPs. Finally, the long-term conservation of nanoparticles by Au photoseeding is presented.
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Affiliation(s)
- Ulf Wiedwald
- Institut für Festkörperphysik, Universität Ulm, 89069 Ulm, Germany
| | - Luyang Han
- Institut für Festkörperphysik, Universität Ulm, 89069 Ulm, Germany
| | - Johannes Biskupek
- Materialwissenschaftliche Elektronenmikroskopie, Universität Ulm, 89069 Ulm, Germany
| | - Ute Kaiser
- Materialwissenschaftliche Elektronenmikroskopie, Universität Ulm, 89069 Ulm, Germany
| | - Paul Ziemann
- Institut für Festkörperphysik, Universität Ulm, 89069 Ulm, Germany
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