1
|
Eggert B, Çakır A, Günzing D, Josten N, Scheibel F, Brand RA, Farle M, Acet M, Wende H, Ollefs K. Formation of precipitates in off-stoichiometric Ni-Mn-Sn Heusler alloys probed through the induced Sn-moment. RSC Adv 2023; 13:18217-18222. [PMID: 37333792 PMCID: PMC10269055 DOI: 10.1039/d3ra01420g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 06/06/2023] [Indexed: 06/20/2023] Open
Abstract
The shell-ferromagnetic effect originates from the segregation process in off-stoichiometric Ni-Mn-based Heusler alloys. In this work, we investigate the precipitation process of L21-ordered Ni2MnSn and L10-ordered NiMn in off-stoichiometric Ni50Mn45Sn5 during temper annealing, by X-ray diffraction (XRD) and 119Sn Mössbauer spectroscopy. While XRD probes long-range ordering of the lattice structure, Mössbauer spectroscopy probes nearest-neighbour interactions, reflected in the induced Sn magnetic moment. As shown in this work, the induced magnetic Sn moment can be used as a detector for microscopic structural changes and is, therefore, a powerful tool for investigating the formation of nano-precipitates. Similar research can be performed in the future, for example, on different pinning type magnets like Sm-Co or Nd-Fe-B.
Collapse
Affiliation(s)
- Benedikt Eggert
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen Lotharstr. 1 47057 Duisburg Germany
| | - Aslı Çakır
- Department of Metallurgical and Materials Engineering, Muğla Sıtkı Koçman University 48000 Mugla Turkey
| | - Damian Günzing
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen Lotharstr. 1 47057 Duisburg Germany
| | - Nicolas Josten
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen Lotharstr. 1 47057 Duisburg Germany
| | - Franziska Scheibel
- Functional Materials, Institute of Materials Science, Technische Universität Darmstadt 64287 Darmstadt Germany
| | - Richard A Brand
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen Lotharstr. 1 47057 Duisburg Germany
| | - Michael Farle
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen Lotharstr. 1 47057 Duisburg Germany
| | - Mehmet Acet
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen Lotharstr. 1 47057 Duisburg Germany
| | - Heiko Wende
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen Lotharstr. 1 47057 Duisburg Germany
| | - Katharina Ollefs
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen Lotharstr. 1 47057 Duisburg Germany
| |
Collapse
|
2
|
Feggeler T, Meckenstock R, Spoddig D, Schöppner C, Zingsem B, Schaffers T, Ohldag H, Wende H, Farle M, Ney A, Ollefs K. Element-specific visualization of dynamic magnetic coupling in a Co/Py bilayer microstructure. Sci Rep 2022; 12:18724. [PMID: 36333578 PMCID: PMC9636384 DOI: 10.1038/s41598-022-23273-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022] Open
Abstract
We present the element-specific and time resolved visualization of uniform ferromagnetic resonance excitations of a Permalloy (Py) disk–Cobalt (Co) stripe bilayer microstructure. The transverse high frequency component of the resonantly excited magnetization is sampled in the ps regime by a combination of ferromagnetic resonance (FMR) and scanning transmission X-ray microscopy (STXM-FMR) recording snapshots of the local magnetization precession of Py and Co with nanometer spatial resolution. The approach allows us to individually image the resonant dynamic response of each element, and we find that angular momentum is transferred from the Py disk to the Co stripe and vice versa at their respective resonances. The integral (cavity) FMR spectrum of our sample shows an unexpected additional third resonance. This resonance is observed in the STXM-FMR experiments as well. Our microscopic findings suggest that it is governed by magnetic exchange between Py and Co, showing for the Co stripe a difference in relative phase of the magnetization due to stray field influence.
Collapse
|
3
|
Shkodich N, Staab F, Spasova M, Kuskov KV, Durst K, Farle M. Effect of High-Pressure Torsion on the Microstructure and Magnetic Properties of Nanocrystalline CoCrFeNiGa x (x = 0.5, 1.0) High Entropy Alloys. Materials (Basel) 2022; 15:7214. [PMID: 36295283 PMCID: PMC9609683 DOI: 10.3390/ma15207214] [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] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/10/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
In our search for an optimum soft magnet with excellent mechanical properties which can be used in applications centered around "electro mobility", nanocrystalline CoCrFeNiGax (x = 0.5, 1.0) bulk high entropy alloys (HEA) were successfully produced by spark plasma sintering (SPS) at 1073 K of HEA powders produced by high energy ball milling (HEBM). SPS of non-equiatomic CoCrFeNiGa0.5 particles results in the formation of a single-phase fcc bulk HEA, while for the equiatomic CoCrFeNiGa composition a mixture of bcc and fcc phases was found. For both compositions SEM/EDX analysis showed a predominant uniform distribution of the elements with only a small number of Cr-rich precipitates. High pressure torsion (HPT) of the bulk samples led to an increased homogeneity and a grain refinement: i.e., the crystallite size of the single fcc phase of CoCrFeNiGa0.5 decreased by a factor of 3; the crystallite size of the bcc and fcc phases of CoCrFeNiGa-by a factor of 4 and 10, respectively. The lattice strains substantially increased by nearly the same extent. After HPT the saturation magnetization (Ms) of the fcc phase of CoCrFeNiGa0.5 and its Curie temperature increased by 17% (up to 35 Am2/kg) and 31.5% (from 95 K to 125 K), respectively, whereas the coercivity decreased by a factor of 6. The overall Ms of the equiatomic CoCrFeNiGa decreased by 34% and 55% at 10 K and 300 K, respectively. At the same time the coercivity of CoCrFeNiGa increased by 50%. The HPT treatment of SPS-consolidated HEAs increased the Vickers hardness (Hv) by a factor of two (up to 5.632 ± 0.188) only for the non-equiatomic CoCrFeNiGa0.5, while for the equiatomic composition, the Hv remained unchanged (6.343-6.425 GPa).
Collapse
Affiliation(s)
- Natalia Shkodich
- Faculty of Physics and Center of Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Franziska Staab
- Physical Metallurgy, Materials Science Department, Technical University of Darmstadt, 64287 Darmstadt, Germany
| | - Marina Spasova
- Faculty of Physics and Center of Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Kirill V. Kuskov
- Center of Functional Nano-Ceramics, National University of Science and Technology MISIS, 119049 Moscow, Russia
| | - Karsten Durst
- Physical Metallurgy, Materials Science Department, Technical University of Darmstadt, 64287 Darmstadt, Germany
| | - Michael Farle
- Faculty of Physics and Center of Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| |
Collapse
|
4
|
Tao Q, Barbier M, Mockute A, Ritter C, Salikhov R, Wiedwald U, Calder S, Opagiste C, Galera RM, Farle M, Ouisse T, Rosen J. Magnetic phase diagram of (Mo 2/3RE 1/3) 2AlC, RE =Tb and Dy, studied by magnetization, specific heat, and neutron diffraction analysis. J Phys Condens Matter 2022; 34:215801. [PMID: 35259732 DOI: 10.1088/1361-648x/ac5bcf] [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] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
We report the results of magnetization, heat capacity, and neutron diffraction measurements on (Mo2/3RE1/3)2AlC with RE = Dy and Tb. Temperature and field-dependent magnetization as well as heat capacity were measured on a powder sample and on a single crystal allowing the construction of the magnetic field-temperature phase diagram. To study the magnetic structure of each magnetic phase, we applied neutron diffraction in a magnetic field up to 6 T. For (Mo2/3Dy1/3)2AlC in zero field, a spin density wave is stabilized at 16 K, with antiferromagnetic ordering at 13 K. Furthermore, we identify the coexistence of ferromagnetic and antiferromagnetic phases induced by magnetic fields for both RE = Tb and Dy. The origin of the field induced phases is resulting from the competing ferromagnetic and antiferromagnetic interactions.
Collapse
Affiliation(s)
- Quanzheng Tao
- Materials Design Division, Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
| | - Maxime Barbier
- Uni. Grenoble Alpes, CNRS, Grenoble INP, LMGP, F-38000 Grenoble, France
- European Synchrotron Radiation Facility (ESRF), CS 40220, F-38043 Grenoble Cedex 9, France
| | - Aurelija Mockute
- Materials Design Division, Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
- Neutron Scattering Division, Oak Ridge National Laboratory Oak Ridge, TN 37831, United States of America
| | - Clemens Ritter
- Institut Laue-Langevin, BP 156, 38042 Grenoble Cedex 9, France
| | - Ruslan Salikhov
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Ulf Wiedwald
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Stuart Calder
- Neutron Scattering Division, Oak Ridge National Laboratory Oak Ridge, TN 37831, United States of America
| | - Christine Opagiste
- Institut Neel, CNRS, Univ. Grenoble Alpes, Grenoble INP, FR-38000 Grenoble, France
| | - Rose-Marie Galera
- Institut Neel, CNRS, Univ. Grenoble Alpes, Grenoble INP, FR-38000 Grenoble, France
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Thierry Ouisse
- Uni. Grenoble Alpes, CNRS, Grenoble INP, LMGP, F-38000 Grenoble, France
| | - Johanna Rosen
- Materials Design Division, Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
| |
Collapse
|
5
|
Tarasov AS, Tarasov IA, Yakovlev IA, Rautskii MV, Bondarev IA, Lukyanenko AV, Platunov MS, Volochaev MN, Efimov DD, Goikhman AY, Belyaev BA, Baron FA, Shanidze LV, Farle M, Varnakov SN, Ovchinnikov SG, Volkov NV. Asymmetric Interfaces in Epitaxial Off-Stoichiometric Fe 3+xSi 1-x/Ge/Fe 3+xSi 1-x Hybrid Structures: Effect on Magnetic and Electric Transport Properties. Nanomaterials (Basel) 2021; 12:nano12010131. [PMID: 35010081 PMCID: PMC8747018 DOI: 10.3390/nano12010131] [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] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/23/2021] [Accepted: 12/26/2021] [Indexed: 11/26/2022]
Abstract
Three-layer iron-rich Fe3+xSi1−x/Ge/Fe3+xSi1−x (0.2 < x < 0.64) heterostructures on a Si(111) surface with Ge thicknesses of 4 nm and 7 nm were grown by molecular beam epitaxy. Systematic studies of the structural and morphological properties of the synthesized samples have shown that an increase in the Ge thickness causes a prolonged atomic diffusion through the interfaces, which significantly increases the lattice misfits in the Ge/Fe3+xSi1−x heterosystem due to the incorporation of Ge atoms into the Fe3+xSi1−x bottom layer. The resultant lowering of the total free energy caused by the development of the surface roughness results in a transition from an epitaxial to a polycrystalline growth of the upper Fe3+xSi1−x. The average lattice distortion and residual stress of the upper Fe3+xSi1−x were determined by electron diffraction and theoretical calculations to be equivalent to 0.2 GPa for the upper epitaxial layer with a volume misfit of −0.63% compared with a undistorted counterpart. The volume misfit follows the resultant interatomic misfit of |0.42|% with the bottom Ge layer, independently determined by atomic force microscopy. The variation in structural order and morphology significantly changes the magnetic properties of the upper Fe3+xSi1−x layer and leads to a subtle effect on the transport properties of the Ge layer. Both hysteresis loops and FMR spectra differ for the structures with 4 nm and 7 nm Ge layers. The FMR spectra exhibit two distinct absorption lines corresponding to two layers of ferromagnetic Fe3+xSi1−x films. At the same time, a third FMR line appears in the sample with the thicker Ge. The angular dependences of the resonance field of the FMR spectra measured in the plane of the film have a pronounced easy-axis type anisotropy, as well as an anisotropy corresponding to the cubic crystal symmetry of Fe3+xSi1−x, which implies the epitaxial orientation relationship of Fe3+xSi1−x (111)[0−11] || Ge(111)[1−10] || Fe3+xSi1−x (111)[0−11] || Si(111)[1−10]. Calculated from ferromagnetic resonance (FMR) data saturation magnetization exceeds 1000 kA/m. The temperature dependence of the electrical resistivity of a Ge layer with thicknesses of 4 nm and 7 nm is of semiconducting type, which is, however, determined by different transport mechanisms.
Collapse
Affiliation(s)
- Anton S. Tarasov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Institute of Engineering Physics and Radio Electronics, Siberian Federal University, 660041 Krasnoyarsk, Russia
- Correspondence: (A.S.T.); (I.A.T.)
| | - Ivan A. Tarasov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Correspondence: (A.S.T.); (I.A.T.)
| | - Ivan A. Yakovlev
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
| | - Mikhail V. Rautskii
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
| | - Ilya A. Bondarev
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia
| | - Anna V. Lukyanenko
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Institute of Engineering Physics and Radio Electronics, Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Mikhail S. Platunov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Synchrotron Radiation Facility SKIF, Boreskov Institute of Catalysis SB RAS, Nikol’skiy Prospekt 1, 630559 Kol’tsovo, Russia
| | - Mikhail N. Volochaev
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- REC Smart Materials and Biomedical Applications, Immanuel Kant Baltic Federal University, 236041 Kaliningrad, Russia
| | - Dmitriy D. Efimov
- REC Functional Nanomaterials, Immanuel Kant Baltic Federal University, 236016 Kaliningrad, Russia; (D.D.E.); (A.Y.G.)
| | - Aleksandr Yu. Goikhman
- REC Functional Nanomaterials, Immanuel Kant Baltic Federal University, 236016 Kaliningrad, Russia; (D.D.E.); (A.Y.G.)
| | - Boris A. Belyaev
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Institute of Engineering Physics and Radio Electronics, Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Filipp A. Baron
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
| | - Lev V. Shanidze
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia
| | - Michael Farle
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Sergey N. Varnakov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
| | - Sergei G. Ovchinnikov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Institute of Engineering Physics and Radio Electronics, Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Nikita V. Volkov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, 660036 Krasnoyarsk, Russia; (I.A.Y.); (M.V.R.); (I.A.B.); (A.V.L.); (M.S.P.); (M.N.V.); (B.A.B.); (F.A.B.); (L.V.S.); (M.F.); (S.N.V.); (S.G.O.); (N.V.V.)
- Institute of Engineering Physics and Radio Electronics, Siberian Federal University, 660041 Krasnoyarsk, Russia
| |
Collapse
|
6
|
Zhandun VS, Zamkova NG, Draganyuk ON, Shinkorenko AS, Wiedwald U, Ovchinnikov SG, Farle M. The effect of the composition and pressure on the phase stability and electronic, magnetic, and elastic properties of M 2AX (M = Mn, Fe; A = Al, Ga, Si, Ge; X = C, N) phases. Phys Chem Chem Phys 2021; 23:26376-26384. [PMID: 34792064 DOI: 10.1039/d1cp03427h] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The magnetic properties of M2AX (M = Mn, Fe; A = Al, Ga, Si, Ge; X = C, N) phases were studied within DFT-GGA. The magnetic electronic ground state is determined. The investigation of the phase stability of M2AX phases is performed by comparing the total energy of MAX phases to that of the set of competitive phases for calculation of the phase formation enthalpy. As the result of such an approach, we have found one stable compound (Mn2GaC), and seven metastable ones. It is shown that several metastable MAX phases (Mn2AlC, Fe2GaC, Mn2GeC, and Mn2GeN) become stable at a small applied pressure (1.5-7 GPa). The mechanical, electronic and elastic properties of metastable MAX phases are studied.
Collapse
Affiliation(s)
- Vyacheslav S Zhandun
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia.
| | - Natalia G Zamkova
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia. .,Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Oksana N Draganyuk
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia.
| | - Aleksey S Shinkorenko
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia.
| | - Ulf Wiedwald
- Faculty of Physics, University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Sergey G Ovchinnikov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia. .,Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Michael Farle
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia. .,Faculty of Physics, University of Duisburg-Essen, 47057 Duisburg, Germany
| |
Collapse
|
7
|
Nadarajah R, Tasdemir L, Thiel C, Salamon S, Semisalova AS, Wende H, Farle M, Barcikowski S, Erni D, Gökce B. Formation of Fe-Ni Nanoparticle Strands in Macroscopic Polymer Composites: Experiment and Simulation. Nanomaterials (Basel) 2021; 11:2095. [PMID: 34443925 PMCID: PMC8398175 DOI: 10.3390/nano11082095] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 07/13/2021] [Revised: 08/08/2021] [Accepted: 08/12/2021] [Indexed: 02/04/2023]
Abstract
Magnetic-field-induced strand formation of ferromagnetic Fe-Ni nanoparticles in a PMMA-matrix is correlated with the intrinsic material parameters, such as magnetization, particle size, composition, and extrinsic parameters, including magnetic field strength and viscosity. Since various factors can influence strand formation, understanding the composite fabrication process that maintains the strand lengths of Fe-Ni in the generated structures is a fundamental step in predicting the resulting structures. Hence, the critical dimensions of the strands (length, width, spacing, and aspect ratio) are investigated in the experiments and simulated via different intrinsic and extrinsic parameters. Optimal parameters were found by optical microscopy measurements and finite-element simulations using COMSOL for strand formation of Fe50Ni50 nanoparticles. The anisotropic behavior of the aligned strands was successfully characterized through magnetometry measurements. Compared to the unaligned samples, the magnetically aligned strands exhibit enhanced conductivity, increasing the current by a factor of 1000.
Collapse
Affiliation(s)
- Ruksan Nadarajah
- Technical Chemistry I, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitaetsstr. 7, 45141 Essen, Germany; (R.N.); (L.T.); (S.B.)
| | - Leyla Tasdemir
- Technical Chemistry I, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitaetsstr. 7, 45141 Essen, Germany; (R.N.); (L.T.); (S.B.)
| | - Christian Thiel
- General and Theoretical Electrical Engineering (ATE), Center for Nanointegration Duisburg-Essen (CENIDE), University Duisburg-Essen, 47048 Duisburg, Germany; (C.T.); (D.E.)
| | - Soma Salamon
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (S.S.); (A.S.S.); (H.W.); (M.F.)
| | - Anna S. Semisalova
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (S.S.); (A.S.S.); (H.W.); (M.F.)
| | - Heiko Wende
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (S.S.); (A.S.S.); (H.W.); (M.F.)
| | - Michael Farle
- Faculty of Physics, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (S.S.); (A.S.S.); (H.W.); (M.F.)
| | - Stephan Barcikowski
- Technical Chemistry I, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitaetsstr. 7, 45141 Essen, Germany; (R.N.); (L.T.); (S.B.)
| | - Daniel Erni
- General and Theoretical Electrical Engineering (ATE), Center for Nanointegration Duisburg-Essen (CENIDE), University Duisburg-Essen, 47048 Duisburg, Germany; (C.T.); (D.E.)
| | - Bilal Gökce
- Technical Chemistry I, Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitaetsstr. 7, 45141 Essen, Germany; (R.N.); (L.T.); (S.B.)
- Materials Science and Additive Manufacturing, University of Wuppertal, Gaußstr. 20, 42119 Wuppertal, Germany
| |
Collapse
|
8
|
Nadarajah R, Landers J, Salamon S, Koch D, Tahir S, Doñate-Buendía C, Zingsem B, Dunin-Borkowski RE, Donner W, Farle M, Wende H, Gökce B. Towards laser printing of magnetocaloric structures by inducing a magnetic phase transition in iron-rhodium nanoparticles. Sci Rep 2021; 11:13719. [PMID: 34215776 PMCID: PMC8253782 DOI: 10.1038/s41598-021-92760-5] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 06/11/2021] [Indexed: 11/24/2022] Open
Abstract
The development of magnetocaloric materials represents an approach to enable efficient and environmentally friendly refrigeration. It is envisioned as a key technology to reduce CO2 emissions of air conditioning and cooling systems. Fe-Rh has been shown to be one of the best-suited materials in terms of heat exchange per material volume. However, the Fe-Rh magnetocaloric response depends on its composition. Hence, the adaptation of material processing routes that preserve the Fe-Rh magnetocaloric response in the generated structures is a fundamental step towards the industrial development of this cooling technology. To address this challenge, the temperature-dependent properties of laser synthesized Fe-Rh nanoparticles and the laser printing of Fe-Rh nanoparticle inks are studied to generate 2D magnetocaloric structures that are potentially interesting for applications such as waste heat management of compact electrical appliances or thermal diodes, switches, and printable magnetocaloric media. The magnetization and temperature dependence of the ink's γ-FeRh to B2-FeRh magnetic transition is analyzed throughout the complete process, finding a linear increase of the magnetization M (0.8 T, 300 K) up to 96 Am2/kg with ca. 90% of the γ-FeRh being transformed permanently into the B2-phase. In 2D structures, magnetization values of M (0.8 T, 300 K) ≈ 11 Am2/kg could be reached by laser sintering, yielding partial conversion to the B2-phase equivalent to long-time heating temperature of app. 600 K, via this treatment. Thus, the proposed procedure constitutes a robust route to achieve the generation of magnetocaloric structures.
Collapse
Affiliation(s)
| | - Joachim Landers
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057, Duisburg, Germany
| | - Soma Salamon
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057, Duisburg, Germany
| | - David Koch
- Institute of Materials Science, Technical University of Darmstadt, Alarich-Weiss-Strasse 2, 64287, Darmstadt, Germany
| | - Shabbir Tahir
- Universitätsstr. 7, 45141, Essen, Germany
- Materials Science and Additive Manufacturing, University of Wuppertal, Gaußstr. 20, 42119, Wuppertal, Germany
| | - Carlos Doñate-Buendía
- Universitätsstr. 7, 45141, Essen, Germany
- Materials Science and Additive Manufacturing, University of Wuppertal, Gaußstr. 20, 42119, Wuppertal, Germany
| | - Benjamin Zingsem
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057, Duisburg, Germany
- Ernst Ruska-Centre for Microscopy and Spectroscopy With Electrons and Peter Grünberg Institute, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
| | - Rafal E Dunin-Borkowski
- Ernst Ruska-Centre for Microscopy and Spectroscopy With Electrons and Peter Grünberg Institute, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
| | - Wolfgang Donner
- Institute of Materials Science, Technical University of Darmstadt, Alarich-Weiss-Strasse 2, 64287, Darmstadt, Germany
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057, Duisburg, Germany
| | - Heiko Wende
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057, Duisburg, Germany
| | - Bilal Gökce
- Universitätsstr. 7, 45141, Essen, Germany.
- Materials Science and Additive Manufacturing, University of Wuppertal, Gaußstr. 20, 42119, Wuppertal, Germany.
| |
Collapse
|
9
|
Efremova MV, Spasova M, Heidelmann M, Grebennikov IS, Li ZA, Garanina AS, Tcareva IO, Savchenko AG, Farle M, Klyachko NL, Majouga AG, Wiedwald U. Room temperature synthesized solid solution AuFe nanoparticles and their transformation into Au/Fe Janus nanocrystals. Nanoscale 2021; 13:10402-10413. [PMID: 34096958 DOI: 10.1039/d1nr00383f] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Solid solution AuFe nanoparticles were synthesized for the first time under ambient conditions by an adapted method previously established for the Fe3O4-Au core-shell morphology. These AuFe particles preserved the fcc structure of Au incorporated with paramagnetic Fe atoms. The metastable AuFe can be segregated by transformation into Janus Au/Fe particles with bcc Fe and fcc Au upon annealing. The ferromagnetic Fe was epitaxially grown on low index fcc Au planes. This preparation route delivers new perspective materials for magnetoplasmonics and biomedical applications and suggests the reconsideration of existing protocols for magnetite-gold core-shell synthesis.
Collapse
Affiliation(s)
- Maria V Efremova
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russian Federation
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Myrovali E, Papadopoulos K, Iglesias I, Spasova M, Farle M, Wiedwald U, Angelakeris M. Long-Range Ordering Effects in Magnetic Nanoparticles. ACS Appl Mater Interfaces 2021; 13:21602-21612. [PMID: 33929817 DOI: 10.1021/acsami.1c01820] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The challenge for synthesizing magnetic nanoparticle chains may be achieved under the application of fixation fields, which are the externally applied fields, enhancing collective magnetic features due to adequate control of dipolar interactions among magnetic nanoparticles. However, relatively little attention has been devoted to how size, concentration of magnetic nanoparticles, and intensity of an external magnetic field affect the evolution of chain structures and collective magnetic features. Here, iron oxide nanoparticles are developed by the coprecipitation method at diameters below (10 and 20 nm) and above (50 and 80 nm) their superparamagnetic limit (at about 25 nm) and then are subjected to a tunable fixation field (40-400 mT). Eventually, the fixation field dictates smaller particles to form chain structures in two steps, first forming clusters and then guiding chain formation via "cluster-cluster" interactions, whereas larger particles readily form chains via "particle-particle" interactions. In both cases, dipolar interactions between the neighboring nanoparticles augment, leading to a substantial increase in their collective magnetic features which in turn results in magnetic particle hyperthermia efficiency enhancement of up to one order of magnitude. This study provides new perspectives for magnetic nanoparticles by arranging them in chain formulations as enhanced performance magnetic actors in magnetically driven magnetic applications.
Collapse
Affiliation(s)
- Eirini Myrovali
- School of Physics, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
- Magnetic Nanostructure Characterization: Technology and Applications, CIRI-AUTH, Thessaloniki 57001, Greece
| | - Kyrillos Papadopoulos
- School of Physics, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
- Magnetic Nanostructure Characterization: Technology and Applications, CIRI-AUTH, Thessaloniki 57001, Greece
| | - Irene Iglesias
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Duisburg 47048, Germany
| | - Marina Spasova
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Duisburg 47048, Germany
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Duisburg 47048, Germany
| | - Ulf Wiedwald
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Duisburg 47048, Germany
| | - Makis Angelakeris
- School of Physics, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
- Magnetic Nanostructure Characterization: Technology and Applications, CIRI-AUTH, Thessaloniki 57001, Greece
| |
Collapse
|
11
|
Heigl M, Koraltan S, Vaňatka M, Kraft R, Abert C, Vogler C, Semisalova A, Che P, Ullrich A, Schmidt T, Hintermayr J, Grundler D, Farle M, Urbánek M, Suess D, Albrecht M. Dipolar-stabilized first and second-order antiskyrmions in ferrimagnetic multilayers. Nat Commun 2021; 12:2611. [PMID: 33972515 PMCID: PMC8110839 DOI: 10.1038/s41467-021-22600-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/15/2021] [Indexed: 02/03/2023] Open
Abstract
Skyrmions and antiskyrmions are topologically protected spin structures with opposite vorticities. Particularly in coexisting phases, these two types of magnetic quasi-particles may show fascinating physics and potential for spintronic devices. While skyrmions are observed in a wide range of materials, until now antiskyrmions were exclusive to materials with D2d symmetry. In this work, we show first and second-order antiskyrmions stabilized by magnetic dipole-dipole interaction in Fe/Gd-based multilayers. We modify the magnetic properties of the multilayers by Ir insertion layers. Using Lorentz transmission electron microscopy imaging, we observe coexisting antiskyrmions, Bloch skyrmions, and type-2 bubbles and determine the range of material properties and magnetic fields where the different spin objects form and dissipate. We perform micromagnetic simulations to obtain more insight into the studied system and conclude that the reduction of saturation magnetization and uniaxial magnetic anisotropy leads to the existence of this zoo of different spin objects and that they are primarily stabilized by dipolar interaction.
Collapse
Affiliation(s)
- Michael Heigl
- Institute of Physics, University of Augsburg, Augsburg, Germany.
| | - Sabri Koraltan
- Faculty of Physics, University of Vienna, Vienna, Austria
| | - Marek Vaňatka
- CEITEC BUT, Brno University of Technology, Brno, Czech Republic
| | - Robert Kraft
- Faculty of Physics, University of Vienna, Vienna, Austria
| | - Claas Abert
- Faculty of Physics, University of Vienna, Vienna, Austria
- Research Platform MMM Mathematics - Magnetism - Materials, University of Vienna, Vienna, Austria
| | | | - Anna Semisalova
- Center for Nanointegration and Faculty of Physics, University of Duisburg-Essen, Duisburg, Germany
| | - Ping Che
- Laboratory of Nanoscale Magnetic Materials and Magnonics, Institute of Materials (IMX), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Aladin Ullrich
- Institute of Physics, University of Augsburg, Augsburg, Germany
| | - Timo Schmidt
- Institute of Physics, University of Augsburg, Augsburg, Germany
| | | | - Dirk Grundler
- Laboratory of Nanoscale Magnetic Materials and Magnonics, Institute of Materials (IMX), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Institute of Microengineering (IMT), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Michael Farle
- Center for Nanointegration and Faculty of Physics, University of Duisburg-Essen, Duisburg, Germany
| | - Michal Urbánek
- CEITEC BUT, Brno University of Technology, Brno, Czech Republic
| | - Dieter Suess
- Faculty of Physics, University of Vienna, Vienna, Austria
- Research Platform MMM Mathematics - Magnetism - Materials, University of Vienna, Vienna, Austria
| | | |
Collapse
|
12
|
Nikitin AA, Yurenya AY, Zatsepin TS, Aparin IO, Chekhonin VP, Majouga AG, Farle M, Wiedwald U, Abakumov MA. Magnetic Nanoparticles as a Tool for Remote DNA Manipulations at a Single-Molecule Level. ACS Appl Mater Interfaces 2021; 13:14458-14469. [PMID: 33740372 DOI: 10.1021/acsami.0c21002] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Remote control of cells and single molecules by magnetic nanoparticles in nonheating external magnetic fields is a perspective approach for many applications such as cancer treatment and enzyme activity regulation. However, the possibility and mechanisms of direct effects of small individual magnetic nanoparticles on such processes in magneto-mechanical experiments still remain unclear. In this work, we have shown remote-controlled mechanical dissociation of short DNA duplexes (18-60 bp) under the influence of nonheating low-frequency alternating magnetic fields using individual 11 nm magnetic nanoparticles. The developed technique allows (1) simultaneous manipulation of millions of individual DNA molecules and (2) evaluation of energies of intermolecular interactions in short DNA duplexes or in other molecules. Finally, we have shown that DNA duplexes dissociation is mediated by mechanical stress and produced by the movement of magnetic nanoparticles in magnetic fields, but not by local overheating. The presented technique opens a new avenue for high-precision manipulation of DNA and generation of biosensors for quantification of energies of intermolecular interaction.
Collapse
Affiliation(s)
- Aleksey A Nikitin
- National University of Science and Technology (MISIS), Moscow 119049, Russia
- M. V. Lomonosov Moscow State University, Moscow 119991, Russia
| | - Anton Yu Yurenya
- M. V. Lomonosov Moscow State University, Moscow 119991, Russia
- National Research Center "Kurchatov Institute", Moscow 123098, Russia
| | - Timofei S Zatsepin
- M. V. Lomonosov Moscow State University, Moscow 119991, Russia
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Ilya O Aparin
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Vladimir P Chekhonin
- Department of Medical Nanobiotechnology, N. I. Pirogov Russian National Research Medical University, Moscow 117997, Russia
| | - Alexander G Majouga
- National University of Science and Technology (MISIS), Moscow 119049, Russia
- M. V. Lomonosov Moscow State University, Moscow 119991, Russia
- D. Mendeleev University of Chemical Technology of Russia, Moscow 125047, Russia
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Duisburg 47057, Germany
| | - Ulf Wiedwald
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Duisburg 47057, Germany
| | - Maxim A Abakumov
- National University of Science and Technology (MISIS), Moscow 119049, Russia
- Department of Medical Nanobiotechnology, N. I. Pirogov Russian National Research Medical University, Moscow 117997, Russia
| |
Collapse
|
13
|
Nadarajah R, Tahir S, Landers J, Koch D, Semisalova AS, Wiemeler J, El-Zoka A, Kim SH, Utzat D, Möller R, Gault B, Wende H, Farle M, Gökce B. Controlling the Oxidation of Magnetic and Electrically Conductive Solid-Solution Iron-Rhodium Nanoparticles Synthesized by Laser Ablation in Liquids. Nanomaterials (Basel) 2020; 10:E2362. [PMID: 33261038 PMCID: PMC7760681 DOI: 10.3390/nano10122362] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [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: 10/23/2020] [Revised: 11/18/2020] [Accepted: 11/23/2020] [Indexed: 01/26/2023]
Abstract
This study focuses on the synthesis of FeRh nanoparticles via pulsed laser ablation in liquid and on controlling the oxidation of the synthesized nanoparticles. Formation of monomodal γ-FeRh nanoparticles was confirmed by transmission electron microscopy (TEM) and their composition confirmed by atom probe tomography (APT). For these particles, three major contributors to oxidation were analysed: (1) dissolved oxygen in the organic solvents, (2) the bound oxygen in the solvent and (3) oxygen in the atmosphere above the solvent. The decrease of oxidation for optimized ablation conditions was confirmed through energy-dispersive X-ray (EDX) and Mössbauer spectroscopy. Furthermore, the time dependence of oxidation was monitored for dried FeRh nanoparticles powders using ferromagnetic resonance spectroscopy (FMR). By magnetophoretic separation, B2-FeRh nanoparticles could be extracted from the solution and characteristic differences of nanostrand formation between γ-FeRh and B2-FeRh nanoparticles were observed.
Collapse
Affiliation(s)
- Ruksan Nadarajah
- Technical Chemistry I and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitaetsstr. 7, 45141 Essen, Germany; (R.N.); (S.T.)
| | - Shabbir Tahir
- Technical Chemistry I and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitaetsstr. 7, 45141 Essen, Germany; (R.N.); (S.T.)
| | - Joachim Landers
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (J.L.); (A.S.S.); (J.W.); (D.U.); (R.M.); (H.W.); (M.F.)
| | - David Koch
- Institute of Materials Science, University of Technology, Alarich-Weiss-Strasse 2, 64287 Darmstadt, Germany;
| | - Anna S. Semisalova
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (J.L.); (A.S.S.); (J.W.); (D.U.); (R.M.); (H.W.); (M.F.)
| | - Jonas Wiemeler
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (J.L.); (A.S.S.); (J.W.); (D.U.); (R.M.); (H.W.); (M.F.)
| | - Ayman El-Zoka
- Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Strasse 1, 40237 Düsseldorf, Germany; (A.E.-Z.); (S.-H.K.); (B.G.)
| | - Se-Ho Kim
- Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Strasse 1, 40237 Düsseldorf, Germany; (A.E.-Z.); (S.-H.K.); (B.G.)
| | - Detlef Utzat
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (J.L.); (A.S.S.); (J.W.); (D.U.); (R.M.); (H.W.); (M.F.)
| | - Rolf Möller
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (J.L.); (A.S.S.); (J.W.); (D.U.); (R.M.); (H.W.); (M.F.)
| | - Baptiste Gault
- Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Strasse 1, 40237 Düsseldorf, Germany; (A.E.-Z.); (S.-H.K.); (B.G.)
- Department of Materials, Royal School of Mines, Imperial College London, London SW7 2AZ, UK
| | - Heiko Wende
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (J.L.); (A.S.S.); (J.W.); (D.U.); (R.M.); (H.W.); (M.F.)
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany; (J.L.); (A.S.S.); (J.W.); (D.U.); (R.M.); (H.W.); (M.F.)
| | - Bilal Gökce
- Technical Chemistry I and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitaetsstr. 7, 45141 Essen, Germany; (R.N.); (S.T.)
| |
Collapse
|
14
|
Chai K, Li ZA, Liu R, Zou B, Farle M, Li J. Dynamics of chiral state transitions and relaxations in an FeGe thin plate via in situ Lorentz microscopy. Nanoscale 2020; 12:14919-14925. [PMID: 32638795 DOI: 10.1039/d0nr03278f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Studying the magnetic transition between different topological spin textures in noncentrosymmetric magnets under external stimuli is an important topic in chiral magnetism. Here, using in situ Lorentz transmission electron microscopy (LTEM) we directly visualize the thermal-driven magnetic transitions and dynamic characteristics in FeGe thin plates. A novel protocol-dependent phase diagram of FeGe thin plates was obtained via pulsed laser excitation. Moreover, by setting the appropriate specimen temperature, the relaxation of chiral magnetic states in FeGe specimens was recorded and analyzed with an Arrhenius-type relaxation mechanism. We present the field-dependent activation energy barriers for chiral state transitions and the magnetic transition pathways of these spin textures for FeGe thin plates. Our results unveil the effects of thermal excitation on the topological spin texture transitions and provide useful information about magnetic dynamics of chiral magnetic state relaxation.
Collapse
Affiliation(s)
- Ke Chai
- Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China. and Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences, Beijing 100190, China
| | - Zi-An Li
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences, Beijing 100190, China
| | - Ruibin Liu
- Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China.
| | - Bingsuo Zou
- Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China. and Center on Nano-energy Research, School of Physical Science and Technology, Guangxi University, Nanning, 530004, China
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Jianqi Li
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences, Beijing 100190, China and Yangtze River Delta Physics Research Center Co., Ltd. - Liyang, Jiangsu, 213300, China and Songshan Lake Materials Laboratory - Dongguan, Guangdong, 523808, China
| |
Collapse
|
15
|
Nalench YA, Shchetinin IV, Skorikov AS, Mogilnikov PS, Farle M, Savchenko AG, Majouga AG, Abakumov MA, Wiedwald U. Unravelling the nucleation, growth, and faceting of magnetite-gold nanohybrids. J Mater Chem B 2020; 8:3886-3895. [PMID: 32227007 DOI: 10.1039/c9tb02721a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The chemical synthesis of nanoparticles with a preassigned size and shape is important for an optimized performance in any application. Therefore, systematic monitoring of the synthesis is required for the control and detailed understanding of the nucleation and growth of the nanoparticles. Here, we study Fe3O4-Au hybrid nanoparticles in detail using probes of the reaction mixture during synthesis and their thorough characterization. The proposed approach eliminates the problem of repeatability and reproducibility of the chemical synthesis and was carried out using laboratory equipment (standard transmission electron microscopy, X-ray diffraction, and magnetometry) for typically 10 μL samples instead of, for example, a dedicated synthesis and inspection at a synchrotron radiation facility. From the three independent experimental techniques we extract the nanoparticle size at 12 stages of the synthesis. These diameters show identical trends and good quantitative agreement. Two consecutive processes occur during the synthesis of Fe3O4-Au nanoparticles, the nucleation and the growth of spherical Fe3O4 nanoparticles on the surface of Au seeds during the heating stage and their faceting towards octahedral shape during reflux. The final nanoparticles with sizes of 15 nm Fe3O4 and 4 nm Au exhibit superparamagnetic behavior at ambient temperature. These are high-quality, close to stoichiometric Fe3O4 nanocrystals with nearly volumetric magnetic behavior as confirmed by the presence of the Verwey transition. Understanding the processes occurring during the synthesis allows the nanoparticle size and shape to be adjusted, improving their capabilities in biomedical applications.
Collapse
Affiliation(s)
- Yulia A Nalench
- National University of Science and Technology "MISIS", Moscow, 119049, Russia and Department of Medical Nanobiotechnology, Russian National Research Medical University, Moscow, 117997, Russia.
| | - Igor V Shchetinin
- National University of Science and Technology "MISIS", Moscow, 119049, Russia
| | | | - Pavel S Mogilnikov
- National University of Science and Technology "MISIS", Moscow, 119049, Russia
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Duisburg, 47057, Germany.
| | | | - Alexander G Majouga
- National University of Science and Technology "MISIS", Moscow, 119049, Russia and Lomonosov Moscow State University, Moscow, 119991, Russia and D. Mendeleev University of Chemical Technology of Russia, Moscow, 125047, Russia
| | - Maxim A Abakumov
- National University of Science and Technology "MISIS", Moscow, 119049, Russia and Department of Medical Nanobiotechnology, Russian National Research Medical University, Moscow, 117997, Russia.
| | - Ulf Wiedwald
- National University of Science and Technology "MISIS", Moscow, 119049, Russia and Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Duisburg, 47057, Germany.
| |
Collapse
|
16
|
Schaffers T, Feggeler T, Pile S, Meckenstock R, Buchner M, Spoddig D, Ney V, Farle M, Wende H, Wintz S, Weigand M, Ohldag H, Ollefs K, Ney A. Extracting the Dynamic Magnetic Contrast in Time-Resolved X-ray Transmission Microscopy. Nanomaterials (Basel) 2019; 9:nano9070940. [PMID: 31261780 PMCID: PMC6669469 DOI: 10.3390/nano9070940] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 05/28/2019] [Revised: 06/18/2019] [Accepted: 06/24/2019] [Indexed: 11/16/2022]
Abstract
Using a time-resolved detection scheme in scanning transmission X-ray microscopy (STXM), we measured element resolved ferromagnetic resonance (FMR) at microwave frequencies up to 10 GHz and a spatial resolution down to 20 nm at two different synchrotrons. We present different methods to separate the contribution of the background from the dynamic magnetic contrast based on the X-ray magnetic circular dichroism (XMCD) effect. The relative phase between the GHz microwave excitation and the X-ray pulses generated by the synchrotron, as well as the opening angle of the precession at FMR can be quantified. A detailed analysis for homogeneous and inhomogeneous magnetic excitations demonstrates that the dynamic contrast indeed behaves as the usual XMCD effect. The dynamic magnetic contrast in time-resolved STXM has the potential be a powerful tool to study the linear and nonlinear, magnetic excitations in magnetic micro- and nano-structures with unique spatial-temporal resolution in combination with element selectivity.
Collapse
Affiliation(s)
- Taddäus Schaffers
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, 4040 Linz, Austria.
| | - Thomas Feggeler
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Santa Pile
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, 4040 Linz, Austria
| | - Ralf Meckenstock
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Martin Buchner
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, 4040 Linz, Austria
| | - Detlef Spoddig
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Verena Ney
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, 4040 Linz, Austria
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Heiko Wende
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Sebastian Wintz
- Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
- Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
| | - Markus Weigand
- Max-Planck-Institut für Intelligente Systeme, 70569 Stuttgart, Germany
| | - Hendrik Ohldag
- Stanford Synchrotron Radiation Laboratory, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Katharina Ollefs
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | - Andreas Ney
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, 4040 Linz, Austria.
| |
Collapse
|
17
|
Testa-Anta M, Liébana-Viñas S, Rivas-Murias B, Rodríguez González B, Farle M, Salgueiriño V. Shaping iron oxide nanocrystals for magnetic separation applications. Nanoscale 2018; 10:20462-20467. [PMID: 30379181 DOI: 10.1039/c8nr05864d] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Iron oxide nanostructures are attractive for a variety of bio-related applications given their wide range of magnetic properties. Here, we report on the study of the magnetophoretic mobility of octapod-shaped nanocrystals, which we relate to stoichiometry, quality and elongation in the 111 direction of these cubic structures. This special morphology combines magnetocrystalline anisotropies, increases shape anisotropy and hinders the formation of an epitaxial wüstite-magnetite interface. As a result, one obtains nanocrystals with large magnetic susceptibility and small coercivity, that is, with optimum characteristics for magnetic guidance, separation, and drug delivery, due to the increased magnetophoretic mobility displayed.
Collapse
Affiliation(s)
- Martín Testa-Anta
- Departamento de Física Aplicada, Universidade de Vigo, 36310 Vigo, Spain.
| | | | | | | | | | | |
Collapse
|
18
|
Giannopoulos G, Barucca G, Kaidatzis A, Psycharis V, Salikhov R, Farle M, Koutsouflakis E, Niarchos D, Mehta A, Scuderi M, Nicotra G, Spinella C, Laureti S, Varvaro G. L1 0-FeNi films on Au-Cu-Ni buffer-layer: a high-throughput combinatorial study. Sci Rep 2018; 8:15919. [PMID: 30374113 PMCID: PMC6206008 DOI: 10.1038/s41598-018-34296-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 10/12/2018] [Indexed: 11/25/2022] Open
Abstract
The fct L10-FeNi alloy is a promising candidate for the development of high performance critical-elements-free magnetic materials. Among the different materials, the Au-Cu-Ni alloy has resulted very promising; however, a detailed investigation of the effect of the buffer-layer composition on the formation of the hard FeNi phase is still missing. To accelerate the search of the best Au-Cu-Ni composition, a combinatorial approach based on High-Throughput (HT) experimental methods has been exploited in this paper. HT magnetic characterization methods revealed the presence of a hard magnetic phase with an out-of-plane easy-axis, whose coercivity increases from 0.49 kOe up to 1.30 kOe as the Au content of the Cu-Au-Ni buffer-layer decreases. Similarly, the out-of-plane magneto-crystalline anisotropy energy density increases from 0.12 to 0.35 MJ/m3. This anisotropy is attributed to the partial formation of the L10 FeNi phase induced by the buffer-layer. In the range of compositions we investigated, the buffer-layer structure does not change significantly and the modulation of the magnetic properties with the Au content in the combinatorial layer is mainly related to the different nature and extent of interlayer diffusion processes, which have a great impact on the formation and order degree of the L10 FeNi phase.
Collapse
Affiliation(s)
- G Giannopoulos
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Athens, Greece.
| | - G Barucca
- Università Politecnica delle Marche, Dipartimento SIMAU, Via Brecce Bianche 12, Ancona, 60131, Italy.
| | - A Kaidatzis
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Athens, Greece
| | - V Psycharis
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Athens, Greece
| | - R Salikhov
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057, Duisburg, Germany
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, 420029, Kazan, Russian Federation
| | - M Farle
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057, Duisburg, Germany
- Center for Functionalized Magnetic Materials (FunMagMa), Immanuel Kant Baltic Federal University, Kaliningrad, Russian Federation
| | - E Koutsouflakis
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Athens, Greece
| | - D Niarchos
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, Athens, Greece
| | - A Mehta
- SLAC National Accelerator Laboratory- Stanford University, Menlo Park, California, USA
| | - M Scuderi
- IMM-CNR, VII strada 5, 95121, Catania, Italy
| | - G Nicotra
- IMM-CNR, VII strada 5, 95121, Catania, Italy
| | - C Spinella
- IMM-CNR, VII strada 5, 95121, Catania, Italy
| | - S Laureti
- Istituto di Struttura della Materia, CNR, Monterotondo Scalo, Roma, Italy
| | - G Varvaro
- Istituto di Struttura della Materia, CNR, Monterotondo Scalo, Roma, Italy
| |
Collapse
|
19
|
Efremova MV, Nalench YA, Myrovali E, Garanina AS, Grebennikov IS, Gifer PK, Abakumov MA, Spasova M, Angelakeris M, Savchenko AG, Farle M, Klyachko NL, Majouga AG, Wiedwald U. Size-selected Fe 3O 4-Au hybrid nanoparticles for improved magnetism-based theranostics. Beilstein J Nanotechnol 2018; 9:2684-2699. [PMID: 30416920 PMCID: PMC6204820 DOI: 10.3762/bjnano.9.251] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 09/17/2018] [Indexed: 05/24/2023]
Abstract
Size-selected Fe3O4-Au hybrid nanoparticles with diameters of 6-44 nm (Fe3O4) and 3-11 nm (Au) were prepared by high temperature, wet chemical synthesis. High-quality Fe3O4 nanocrystals with bulk-like magnetic behavior were obtained as confirmed by the presence of the Verwey transition. The 25 nm diameter Fe3O4-Au hybrid nanomaterial sample (in aqueous and agarose phantom systems) showed the best characteristics for application as contrast agents in magnetic resonance imaging and for local heating using magnetic particle hyperthermia. Due to the octahedral shape and the large saturation magnetization of the magnetite particles, we obtained an extraordinarily high r 2-relaxivity of 495 mM-1·s-1 along with a specific loss power of 617 W·gFe -1 and 327 W·gFe -1 for hyperthermia in aqueous and agarose systems, respectively. The functional in vitro hyperthermia test for the 4T1 mouse breast cancer cell line demonstrated 80% and 100% cell death for immediate exposure and after precultivation of the cells for 6 h with 25 nm Fe3O4-Au hybrid nanomaterials, respectively. This confirms that the improved magnetic properties of the bifunctional particles present a next step in magnetic-particle-based theranostics.
Collapse
Affiliation(s)
- Maria V Efremova
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
| | - Yulia A Nalench
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
| | - Eirini Myrovali
- Physics Department, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece
| | - Anastasiia S Garanina
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
| | - Ivan S Grebennikov
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
| | - Polina K Gifer
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
| | - Maxim A Abakumov
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
- Department of Medical Nanobiotechnology, Russian National Research Medical University, Moscow, 117997, Russia
| | - Marina Spasova
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen (CENIDE), Duisburg, 47057, Germany
| | - Makis Angelakeris
- Physics Department, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece
| | | | - Michael Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen (CENIDE), Duisburg, 47057, Germany
| | - Natalia L Klyachko
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
| | - Alexander G Majouga
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russia
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
- D. Mendeleev University of Chemical Technology of Russia, Moscow, 125047, Russia
| | - Ulf Wiedwald
- National University of Science and Technology «MISIS», Moscow, 119049, Russia
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen (CENIDE), Duisburg, 47057, Germany
| |
Collapse
|
20
|
Efremova MV, Naumenko VA, Spasova M, Garanina AS, Abakumov MA, Blokhina AD, Melnikov PA, Prelovskaya AO, Heidelmann M, Li ZA, Ma Z, Shchetinin IV, Golovin YI, Kireev II, Savchenko AG, Chekhonin VP, Klyachko NL, Farle M, Majouga AG, Wiedwald U. Magnetite-Gold nanohybrids as ideal all-in-one platforms for theranostics. Sci Rep 2018; 8:11295. [PMID: 30050080 PMCID: PMC6062557 DOI: 10.1038/s41598-018-29618-w] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 07/16/2018] [Indexed: 12/21/2022] Open
Abstract
High-quality, 25 nm octahedral-shaped Fe3O4 magnetite nanocrystals are epitaxially grown on 9 nm Au seed nanoparticles using a modified wet-chemical synthesis. These Fe3O4-Au Janus nanoparticles exhibit bulk-like magnetic properties. Due to their high magnetization and octahedral shape, the hybrids show superior in vitro and in vivo T2 relaxivity for magnetic resonance imaging as compared to other types of Fe3O4-Au hybrids and commercial contrast agents. The nanoparticles provide two functional surfaces for theranostic applications. For the first time, Fe3O4-Au hybrids are conjugated with two fluorescent dyes or the combination of drug and dye allowing the simultaneous tracking of the nanoparticle vehicle and the drug cargo in vitro and in vivo. The delivery to tumors and payload release are demonstrated in real time by intravital microscopy. Replacing the dyes by cell-specific molecules and drugs makes the Fe3O4-Au hybrids a unique all-in-one platform for theranostics.
Collapse
Affiliation(s)
- Maria V Efremova
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russian Federation
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation
| | - Victor A Naumenko
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation
| | - Marina Spasova
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Duisburg, 47057, Germany
| | - Anastasiia S Garanina
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russian Federation
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation
| | - Maxim A Abakumov
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation
- Department of Medical Nanobiotechnology, Russian National Research Medical University, Moscow, 117997, Russian Federation
| | - Anastasia D Blokhina
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russian Federation
| | - Pavel A Melnikov
- Department of Fundamental and Applied Neurobiology, Serbsky National Medical Research Center for Psychiatry and Narcology, Ministry of Health and Social Development of the Russian Federation, Moscow, 119034, Russian Federation
| | | | - Markus Heidelmann
- ICAN - Interdisciplinary Center for Analytics on the Nanoscale and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Duisburg, 47057, Germany
| | - Zi-An Li
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Duisburg, 47057, Germany
| | - Zheng Ma
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Duisburg, 47057, Germany
| | - Igor V Shchetinin
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation
| | - Yuri I Golovin
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russian Federation
- Derzhavin Tambov State University, Nanocenter, Tambov, 392000, Russian Federation
| | - Igor I Kireev
- A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russian Federation
| | - Alexander G Savchenko
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation
| | - Vladimir P Chekhonin
- Department of Medical Nanobiotechnology, Russian National Research Medical University, Moscow, 117997, Russian Federation
- Department of Fundamental and Applied Neurobiology, Serbsky National Medical Research Center for Psychiatry and Narcology, Ministry of Health and Social Development of the Russian Federation, Moscow, 119034, Russian Federation
| | - Natalia L Klyachko
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russian Federation
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Duisburg, 47057, Germany
| | - Alexander G Majouga
- Department of Chemistry, Lomonosov Moscow State University, Moscow, 119991, Russian Federation.
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation.
- D. Mendeleev University of Chemical Technology of Russia, Moscow, 125047, Russian Federation.
| | - Ulf Wiedwald
- National University of Science and Technology «MISIS», Moscow, 119049, Russian Federation.
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Duisburg, 47057, Germany.
| |
Collapse
|
21
|
Çakır A, Krenke T, Farle M, Acet M. A variable pole magnet. J Phys Condens Matter 2018; 30:075803. [PMID: 29309275 DOI: 10.1088/1361-648x/aaa5f5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The off-stoichiometric antiferromagnetic Heusler alloy Fe50Mn45Ga5 decomposes and forms ferromagnetic Fe50Mn25Ga25 precipitates embedded in an antiferromagnetic Fe50Mn50 matrix when temper-annealed at temperatures T > 550 K. The ferromagnetism of the precipitates is soft so that the magnetization direction of the non-interacting precipitates in a macroscopic material can be manipulated by locally applied fields so that even two similar poles can form at the ends of a centimeter-long bar. The cause for the soft magnetic behavior is due to the weak AF exchange anisotropy of the cubic Fe50Mn50 matrix and the precipitate.
Collapse
Affiliation(s)
- Aslı Çakır
- Muğla Sıtkı Koçman University, Department of Metallurgical and Materials Engineering, 48000 Muğla, Turkey
| | | | | | | |
Collapse
|
22
|
Novoselova IP, Petruhins A, Wiedwald U, Ingason ÁS, Hase T, Magnus F, Kapaklis V, Palisaitis J, Spasova M, Farle M, Rosen J, Salikhov R. Large uniaxial magnetostriction with sign inversion at the first order phase transition in the nanolaminated Mn 2GaC MAX phase. Sci Rep 2018; 8:2637. [PMID: 29422618 PMCID: PMC5805691 DOI: 10.1038/s41598-018-20903-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 01/23/2018] [Indexed: 11/17/2022] Open
Abstract
In 2013, a new class of inherently nanolaminated magnetic materials, the so called magnetic MAX phases, was discovered. Following predictive material stability calculations, the hexagonal Mn2GaC compound was synthesized as hetero-epitaxial films containing Mn as the exclusive M-element. Recent theoretical and experimental studies suggested a high magnetic ordering temperature and non-collinear antiferromagnetic (AFM) spin states as a result of competitive ferromagnetic and antiferromagnetic exchange interactions. In order to assess the potential for practical applications of Mn2GaC, we have studied the temperature-dependent magnetization, and the magnetoresistive, magnetostrictive as well as magnetocaloric properties of the compound. The material exhibits two magnetic phase transitions. The Néel temperature is TN ~ 507 K, at which the system changes from a collinear AFM state to the paramagnetic state. At Tt = 214 K the material undergoes a first order magnetic phase transition from AFM at higher temperature to a non-collinear AFM spin structure. Both states show large uniaxial c-axis magnetostriction of 450 ppm. Remarkably, the magnetostriction changes sign, being compressive (negative) above Tt and tensile (positive) below the Tt. The sign change of the magnetostriction is accompanied by a sign change in the magnetoresistance indicating a coupling among the spin, lattice and electrical transport properties.
Collapse
Affiliation(s)
- Iuliia P Novoselova
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057, Duisburg, Germany
| | - Andrejs Petruhins
- Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83, Linköping, Sweden
| | - Ulf Wiedwald
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057, Duisburg, Germany.,National University of Science and Technology «MISIS», 119049, Moscow, Russian Federation
| | - Árni Sigurdur Ingason
- Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83, Linköping, Sweden.,Grein Research ehf. Dunhaga 5, Reykjavik, Iceland
| | - Thomas Hase
- Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
| | - Fridrik Magnus
- Science Institute, University of Iceland, Dunhaga 3, IS-107, Reykjavik, Iceland.,Division of Materials Physics, Department of Physics and Astronomy, Uppsala University, Box 516, SE-75121, Uppsala, Sweden
| | - Vassilios Kapaklis
- Division of Materials Physics, Department of Physics and Astronomy, Uppsala University, Box 516, SE-75121, Uppsala, Sweden
| | - Justinas Palisaitis
- Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83, Linköping, Sweden
| | - Marina Spasova
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057, Duisburg, Germany
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057, Duisburg, Germany.,Center for Functionalized Magnetic Materials (FunMagMa), Immanuel Kant Baltic Federal University, Kaliningrad, Russian Federation
| | - Johanna Rosen
- Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83, Linköping, Sweden
| | - Ruslan Salikhov
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057, Duisburg, Germany. .,Zavoisky Physical-Technical Institute, Russian Academy of Sciences, 420029, Kazan, Russian Federation.
| |
Collapse
|
23
|
Ünlü CG, Acet M, Tekgül A, Farle M, Atakan Ş, Lindner J. The Production of Cu Nanoparticles on Large Area Graphene by Sputtering and in-Flight Sintering. Crystal Research and Technology 2017. [DOI: 10.1002/crat.201700149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- C. Gökhan Ünlü
- Department of Biomedical Engineering; Pamukkale University; Denizli TR-20070 Turkey
| | - Mehmet Acet
- Faculty of Physics; University of Duisburg-Essen; Essen D-45141 Germany
| | - Atakan Tekgül
- Department of Physics; Akdeniz University; TR-07058 Antalya Turkey
- Department of Physics; Uludag University; TR-16050 Bursa Turkey
| | - Michael Farle
- Faculty of Physics; University of Duisburg-Essen; Essen D-45141 Germany
| | | | - Jürgen Lindner
- Helmholtz-Zentrum Dresden-Rossendorf; Institut für Ionenstrahlphysik und Materialforschung; Dresden Germany
| |
Collapse
|
24
|
Schaffers T, Meckenstock R, Spoddig D, Feggeler T, Ollefs K, Schöppner C, Bonetti S, Ohldag H, Farle M, Ney A. The combination of micro-resonators with spatially resolved ferromagnetic resonance. Rev Sci Instrum 2017; 88:093703. [PMID: 28964194 DOI: 10.1063/1.4996780] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 07/17/2017] [Indexed: 06/07/2023]
Abstract
We present two new and complementary approaches to realize spatial resolution for ferromagnetic resonance (FMR) on the 100 nm-scale. Both experimental setups utilize lithographically fabricated micro-resonators. They offer a detection sensitivity that is increased by four orders of magnitude compared with resonator-based FMR. In the first setup, the magnetic properties are thermally modulated via the thermal near-field effect generated by the thermal probe of an atomic force microscope. In combination with lock-in detection of the absorbed microwave power in the micro-resonator, a spatial resolution of less than 100 nm is achieved. The second setup is a combination of a micro-resonator with a scanning transmission x-ray microscope (STXM). Here a conventional FMR is excited by the micro-resonator while focused x-rays are used for a time-resolved snap-shot detection of the FMR excitations via the x-ray magnetic circular dichroism effect. This technique allows a lateral resolution of nominally 35 nm given by the STXM. Both experimental setups combine the advantage of low-power FMR excitation in the linear regime with high spatial resolution to study single and coupled nanomagnets. As proof-of-principle experiments, two perpendicular magnetic micro-stripes (5 μm × 1 μm) were grown and their FMR excitations were investigated using both setups.
Collapse
Affiliation(s)
- T Schaffers
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Str. 69, 4040 Linz, Austria
| | - R Meckenstock
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany
| | - D Spoddig
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany
| | - T Feggeler
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany
| | - K Ollefs
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany
| | - C Schöppner
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany
| | - S Bonetti
- Stanford Synchrotron Radiation Laboratory, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - H Ohldag
- Stanford Synchrotron Radiation Laboratory, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - M Farle
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, 47057 Duisburg, Germany
| | - A Ney
- Institute of Semiconductor and Solid State Physics, Johannes Kepler University, Altenberger Str. 69, 4040 Linz, Austria
| |
Collapse
|
25
|
Wang FZ, Salikhov R, Spasova M, Liébana-Viñas S, Bran C, Chen YS, Vazquez M, Farle M, Wiedwald U. Doubling of the magnetic energy product in ferromagnetic nanowires at ambient temperature by capping their tips with an antiferromagnet. Nanotechnology 2017; 28:295402. [PMID: 28589915 DOI: 10.1088/1361-6528/aa77b7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We present an approach to prepare free-standing tips of micrometer-long nanowires electrodeposited in anodic aluminum oxide nanopores. Such open tips can be further processed, e.g. for vertical interconnects of functional layers or for tailoring the magnetization reversal of ferromagnetic nanowires. The magnetic switching of nanowires is usually initiated by vortex or domain formation at the nanowire tips. We show that coating the tips of Fe30Co70 nanowires (diameter 40 nm, length 16 μm) with thin antiferromagnetic Fe50Mn50 capping layers (thickness ≈10 nm) leads to magnetic hardening with a more than doubled energy product at ambient temperature.
Collapse
Affiliation(s)
- F Z Wang
- Faculty of Physics and Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Salikhov R, Reichel L, Zingsem B, Abrudan R, Edström A, Thonig D, Rusz J, Eriksson O, Schultz L, Fähler S, Farle M, Wiedwald U. Enhanced spin-orbit coupling in tetragonally strained Fe-Co-B films. J Phys Condens Matter 2017; 29:275802. [PMID: 28530633 DOI: 10.1088/1361-648x/aa7498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Tetragonally strained interstitial Fe-Co-B alloys were synthesized as epitaxial films grown on a 20 nm thick Au0.55Cu0.45 buffer layer. Different ratios of the perpendicular to in-plane lattice constant c/a = 1.013, 1.034 and 1.02 were stabilized by adding interstitial boron with different concentrations 0, 4, and 10 at.%, respectively. Using ferromagnetic resonance (FMR) and x-ray magnetic circular dichroism (XMCD) we found that the total orbital magnetic moment significantly increases with increasing c/a ratio, indicating that reduced crystal symmetry and interstitial B leads to a noticeable enhancement of the effect of spin-orbit coupling (SOC) in the Fe-Co-B alloys. First-principles calculations reveal that the increase in orbital magnetic moment mainly originates from B impurities in octahedral position and the reduced symmetry around B atoms. These findings offer the possibility to enhance SOC phenomena-namely the magnetocrystalline anisotropy and the orbital moment-by stabilizing anisotropic strain by doping 4 at.% B. Results on the influence of B doping on the Fe-Co film microstructure, their coercive field and magnetic relaxation are also presented.
Collapse
Affiliation(s)
- R Salikhov
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Jin C, Li ZA, Kovács A, Caron J, Zheng F, Rybakov FN, Kiselev NS, Du H, Blügel S, Tian M, Zhang Y, Farle M, Dunin-Borkowski RE. Control of morphology and formation of highly geometrically confined magnetic skyrmions. Nat Commun 2017; 8:15569. [PMID: 28580935 PMCID: PMC5465359 DOI: 10.1038/ncomms15569] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 04/05/2017] [Indexed: 11/09/2022] Open
Abstract
The ability to controllably manipulate magnetic skyrmions, small magnetic whirls with particle-like properties, in nanostructured elements is a prerequisite for incorporating them into spintronic devices. Here, we use state-of-the-art electron holographic imaging to directly visualize the morphology and nucleation of magnetic skyrmions in a wedge-shaped FeGe nanostripe that has a width in the range of 45–150 nm. We find that geometrically-confined skyrmions are able to adopt a wide range of sizes and ellipticities in a nanostripe that are absent in both thin films and bulk materials and can be created from a helical magnetic state with a distorted edge twist in a simple and efficient manner. We perform a theoretical analysis based on a three-dimensional general model of isotropic chiral magnets to confirm our experimental results. The flexibility and ease of formation of geometrically confined magnetic skyrmions may help to optimize the design of skyrmion-based memory devices. Proposals for skyrmion-based high-density memory devices require an understanding of the formation and shape of skyrmions in confined geometries. Here, the authors use electron holography to image magnetic textures in FeGe nanostripes and explore the parameters governing skyrmion morphology.
Collapse
Affiliation(s)
- Chiming Jin
- The Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Science (CAS), Hefei, Anhui Province 230031, China.,Department of Physics, University of Science and Technology of China, Hefei, Anhui Province 230031, China
| | - Zi-An Li
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, Jülich 52425, Germany.,Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, Duisburg 48047, Germany.,Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - András Kovács
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, Jülich 52425, Germany
| | - Jan Caron
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, Jülich 52425, Germany
| | - Fengshan Zheng
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, Jülich 52425, Germany
| | - Filipp N Rybakov
- M.N. Miheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, Ekaterinburg 620990, Russia.,Ural Federal University, Ekaterinburg 620002, Russia.,KTH Royal Institute of Technology, Stockholm SE-10691, Sweden
| | - Nikolai S Kiselev
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, Jülich 52425, Germany
| | - Haifeng Du
- The Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Science (CAS), Hefei, Anhui Province 230031, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Jiangsu Province 210093, China
| | - Stefan Blügel
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, Jülich 52425, Germany
| | - Mingliang Tian
- The Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Science (CAS), Hefei, Anhui Province 230031, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Jiangsu Province 210093, China
| | - Yuheng Zhang
- The Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Science (CAS), Hefei, Anhui Province 230031, China.,Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Jiangsu Province 210093, China
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, Duisburg 48047, Germany.,Center of Functionalized Magnetic Materials, Immanuel Kant Baltic Federal University, Kaliningrad 236041, Russian Federation
| | - Rafal E Dunin-Borkowski
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, Jülich 52425, Germany
| |
Collapse
|
28
|
Li ZA, Zheng F, Tavabi AH, Caron J, Jin C, Du H, Kovács A, Tian M, Farle M, Dunin-Borkowski RE. Magnetic Skyrmion Formation at Lattice Defects and Grain Boundaries Studied by Quantitative Off-Axis Electron Holography. Nano Lett 2017; 17:1395-1401. [PMID: 28125235 DOI: 10.1021/acs.nanolett.6b04280] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We use in situ Lorentz microscopy and off-axis electron holography to investigate the formation and characteristics of skyrmion lattice defects and their relationship to the underlying crystallographic structure of a B20 FeGe thin film. We obtain experimental measurements of spin configurations at grain boundaries, which reveal inversions of crystallographic and magnetic chirality across adjacent grains, resulting in the formation of interface spin stripes at the grain boundaries. In the absence of material defects, we observe that skyrmions lattices possess dislocations and domain boundaries, in analogy to atomic crystals. Moreover, the distorted skyrmions can flexibly change their size and shape to accommodate local geometry, especially at sites of dislocations in the skyrmion lattice. Our findings provide a detailed understanding of the elasticity of topologically protected skyrmions and their correlation with underlying material defects.
Collapse
Affiliation(s)
- Zi-An Li
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen , 47057 Duisburg, Germany
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich , 52425 Jülich, Germany
- Institute of Physics, Chinese Academy of Sciences , 100190 Beijing, China
| | - Fengshan Zheng
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich , 52425 Jülich, Germany
| | - Amir Hossein Tavabi
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich , 52425 Jülich, Germany
| | - Jan Caron
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich , 52425 Jülich, Germany
| | - Chiming Jin
- High Magnetic Field Laboratory, Chinese Academy of Sciences , 230031 Anhui, China
| | - Haifeng Du
- High Magnetic Field Laboratory, Chinese Academy of Sciences , 230031 Anhui, China
| | - András Kovács
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich , 52425 Jülich, Germany
| | - Mingliang Tian
- High Magnetic Field Laboratory, Chinese Academy of Sciences , 230031 Anhui, China
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen , 47057 Duisburg, Germany
- Center for Functionalized Magnetic Materials (FunMagMa), Immanuel Kant Baltic Federal University , Kaliningrad, Russian Federation
| | - Rafal E Dunin-Borkowski
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich , 52425 Jülich, Germany
| |
Collapse
|
29
|
|
30
|
Römer FM, Wiedwald U, Strusch T, Halim J, Mayerberger E, Barsoum MW, Farle M. Controlling the conductivity of Ti3C2MXenes by inductively coupled oxygen and hydrogen plasma treatment and humidity. RSC Adv 2017. [DOI: 10.1039/c6ra27505b] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
With oxygen and hydrogen plasma the resistivity of transparent MXene electrodes can be controlled.
Collapse
Affiliation(s)
- Florian M. Römer
- Faculty of Physics and Center for Nanointegration (CENIDE)
- University of Duisburg-Essen
- 47057 Duisburg
- Germany
| | - Ulf Wiedwald
- Faculty of Physics and Center for Nanointegration (CENIDE)
- University of Duisburg-Essen
- 47057 Duisburg
- Germany
| | - Tanja Strusch
- Faculty of Physics and Center for Nanointegration (CENIDE)
- University of Duisburg-Essen
- 47057 Duisburg
- Germany
| | - Joseph Halim
- Department of Materials Engineering
- LeBow Engineering Center 27-445
- Drexel University
- Philadelphia
- USA
| | - Elisa Mayerberger
- Department of Materials Engineering
- LeBow Engineering Center 27-445
- Drexel University
- Philadelphia
- USA
| | - Michel W. Barsoum
- Department of Materials Engineering
- LeBow Engineering Center 27-445
- Drexel University
- Philadelphia
- USA
| | - Michael Farle
- Faculty of Physics and Center for Nanointegration (CENIDE)
- University of Duisburg-Essen
- 47057 Duisburg
- Germany
| |
Collapse
|
31
|
Palmero EM, Salikhov R, Wiedwald U, Bran C, Spasova M, Vázquez M, Farle M. Enhanced magnetocrystalline anisotropy of Fe30Co70 nanowires by Cu additives and annealing. Nanotechnology 2016; 27:365704. [PMID: 27479573 DOI: 10.1088/0957-4484/27/36/365704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The use of 3d transition metal-based magnetic nanowires (NWs) for permanent magnet applications requires large magnetocrystalline anisotropy energy (MAE), which in combination with the NWs' magnetic shape anisotropy yields magnetic hardening and an enhancement of the magnetic energy product. Here, we report on the significant increase in MAE by 125 kJ m(-3) in Fe30Co70 NWs with diameters of 20-150 nm embedded in anodic aluminum oxide templates by adding 5 at.% Cu and subsequent annealing at 900 K. Ferromagnetic resonance (FMR) reveals that this enhancement of MAE is twice as large as the enhancement of MAE in annealed, but undoped NWs. X-ray diffraction (XRD) analysis suggests that upon annealing the immiscible Cu in FeCo NWs causes a crystal reorientation with respect to the NW axis with a considerable distortion of the bcc FeCo lattice. This strain is most likely the origin of the strongly enhanced MAE.
Collapse
Affiliation(s)
- Ester M Palmero
- Institute of Materials Science of Madrid, CSIC, E-28049 Madrid, Spain. Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, D-47057 Duisburg, Germany
| | | | | | | | | | | | | |
Collapse
|
32
|
Gutfleisch O, Gottschall T, Fries M, Benke D, Radulov I, Skokov KP, Wende H, Gruner M, Acet M, Entel P, Farle M. Mastering hysteresis in magnetocaloric materials. Philos Trans A Math Phys Eng Sci 2016; 374:20150308. [PMID: 27402928 PMCID: PMC4938067 DOI: 10.1098/rsta.2015.0308] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/25/2016] [Indexed: 05/19/2023]
Abstract
Hysteresis is more than just an interesting oddity that occurs in materials with a first-order transition. It is a real obstacle on the path from existing laboratory-scale prototypes of magnetic refrigerators towards commercialization of this potentially disruptive cooling technology. Indeed, the reversibility of the magnetocaloric effect, being essential for magnetic heat pumps, strongly depends on the width of the thermal hysteresis and, therefore, it is necessary to understand the mechanisms causing hysteresis and to find solutions to minimize losses associated with thermal hysteresis in order to maximize the efficiency of magnetic cooling devices. In this work, we discuss the fundamental aspects that can contribute to thermal hysteresis and the strategies that we are developing to at least partially overcome the hysteresis problem in some selected classes of magnetocaloric materials with large application potential. In doing so, we refer to the most relevant classes of magnetic refrigerants La-Fe-Si-, Heusler- and Fe2P-type compounds.This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.
Collapse
Affiliation(s)
- O Gutfleisch
- Materialwissenschaft, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, 64287 Darmstadt, Germany
| | - T Gottschall
- Materialwissenschaft, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, 64287 Darmstadt, Germany
| | - M Fries
- Materialwissenschaft, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, 64287 Darmstadt, Germany
| | - D Benke
- Materialwissenschaft, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, 64287 Darmstadt, Germany
| | - I Radulov
- Materialwissenschaft, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, 64287 Darmstadt, Germany
| | - K P Skokov
- Materialwissenschaft, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, 64287 Darmstadt, Germany
| | - H Wende
- Fakultät für Physik, Universität Duisburg-Essen, Geibelstraße 41, 47057 Duisburg, Germany
| | - M Gruner
- Fakultät für Physik, Universität Duisburg-Essen, Geibelstraße 41, 47057 Duisburg, Germany
| | - M Acet
- Fakultät für Physik, Universität Duisburg-Essen, Geibelstraße 41, 47057 Duisburg, Germany
| | - P Entel
- Fakultät für Physik, Universität Duisburg-Essen, Geibelstraße 41, 47057 Duisburg, Germany
| | - M Farle
- Fakultät für Physik, Universität Duisburg-Essen, Geibelstraße 41, 47057 Duisburg, Germany
| |
Collapse
|
33
|
Çakır A, Acet M, Farle M. Shell-ferromagnetism of nano-Heuslers generated by segregation under magnetic field. Sci Rep 2016; 6:28931. [PMID: 27412644 PMCID: PMC4944126 DOI: 10.1038/srep28931] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 06/13/2016] [Indexed: 11/09/2022] Open
Abstract
We report on a new functional property in an AF martensitic Heusler Ni50Mn45In5, which when annealed at high temperatures under a magnetic field, segregates and forms Ni50Mn25In25 Heusler precipitates embedded in a Ni50Mn50 matrix. The precipitates are paramagnetic whereas the matrix is antiferromagnetic. However, the spins at the interface with the Ni50Mn50 matrix align with the field during their nucleation and growth and become strongly pinned in the direction of the applied field during annealing, whereas the core spins become paramagnetic. This shell-ferromagnetism persists up to 600 K and is so strongly pinned that the remanent magnetization remains unchanged, even when the field is reversed or when the temperature is cycled between low temperatures and close to the annealing temperature.
Collapse
Affiliation(s)
- A Çakır
- Muğla University, Department of Metallurgical and Materials Engineering, 48000 Muğla, Turkey
| | - M Acet
- Faculty of Physics, Duisburg-Essen University, D-47057 Duisburg, Germany
| | - M Farle
- Faculty of Physics, Duisburg-Essen University, D-47057 Duisburg, Germany
| |
Collapse
|
34
|
Çakr Ö, Acet M, Farle M, Wildes A. Magnetic correlations in the magnetocaloric materials Mn3GaC and Mn3GaC0.85N0.15 studied by neutron polarization analysis and neutron depolarization. J Phys Condens Matter 2016; 28:13LT02. [PMID: 26942866 DOI: 10.1088/0953-8984/28/13/13lt02] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Partially substituting carbon by nitrogen in the antiperovskite compound Mn3GaC increases the first order antiferromagnetic/ferromagnetic transition temperature and at the same time causes the high-temperature long-range ferromagnetism to weaken. To show that the weakening is related to the diminishing of ferromagnetic domain formation, we undertake neutron depolarization and neutron polarization analysis experiments on Mn3GaC and Mn3GaC0.85N0.15. Polarization analysis experiments show that strong ferromagnetic correlations are present at high temperatures in the paramagnetic states of both Mn3GaC and Mn3GaC0.85N0.15 and that these correlations vanish in the antiferromagnetic state. Neutron depolarization studies show that above the first order transition temperature, ferromagnetic domain formation is present in Mn3GaC but is absent in Mn3GaC0.85N0.15. The relationship between ferromagnetic domain formation and transitional hysteresis is brought forward for these two important magnetocaloric materials.
Collapse
Affiliation(s)
- Ö Çakr
- Physics Department, Yldz Technical University, TR-34220 Esenler, Istanbul, Turkey. Department of Physics Engineering, Ankara University, TR-06100 Ankara, Turkey
| | | | | | | |
Collapse
|
35
|
Simeonidis K, Liébana-Viñas S, Wiedwald U, Ma Z, Li ZA, Spasova M, Patsia O, Myrovali E, Makridis A, Sakellari D, Tsiaoussis I, Vourlias G, Farle M, Angelakeris M. A versatile large-scale and green process for synthesizing magnetic nanoparticles with tunable magnetic hyperthermia features. RSC Adv 2016. [DOI: 10.1039/c6ra09362k] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Production of functionalized nanoparticles for magnetic hyperthermia by an industrial-scale process.
Collapse
|
36
|
Liébana-Viñas S, Simeonidis K, Wiedwald U, Li ZA, Ma Z, Myrovali E, Makridis A, Sakellari D, Vourlias G, Spasova M, Farle M, Angelakeris M. Optimum nanoscale design in ferrite based nanoparticles for magnetic particle hyperthermia. RSC Adv 2016. [DOI: 10.1039/c6ra17892h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The study demonstrates the multiplex enhancement of the magnetic hyperthermia response by nanoscale design and magnetism tuning without sparing the biocompatibility of iron-oxide.
Collapse
|
37
|
Viñas SL, Salikhov R, Bran C, Palmero EM, Vazquez M, Arvan B, Yao X, Toson P, Fidler J, Spasova M, Wiedwald U, Farle M. Magnetic hardening of Fe30Co70 nanowires. Nanotechnology 2015; 26:415704. [PMID: 26404670 DOI: 10.1088/0957-4484/26/41/415704] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
3d transition metal-based magnetic nanowires (NWs) are currently considered as potential candidates for alternative rare-earth-free alloys as novel permanent magnets. Here, we report on the magnetic hardening of Fe30Co70 nanowires in anodic aluminium oxide templates with diameters of 20 nm and 40 nm (length 6 μm and 7.5 μm, respectively) by means of magnetic pinning at the tips of the NWs. We observe that a 3-4 nm naturally formed ferrimagnetic FeCo oxide layer covering the tip of the FeCo NW increases the coercive field by 20%, indicating that domain wall nucleation starts at the tip of the magnetic NW. Ferromagnetic resonance (FMR) measurements were used to quantify the magnetic uniaxial anisotropy energy of the samples. Micromagnetic simulations support our experimental findings, showing that the increase of the coercive field can be achieved by controlling domain wall nucleation using magnetic materials with antiferromagnetic exchange coupling, i.e. antiferromagnets or ferrimagnets, as a capping layer at the nanowire tips.
Collapse
Affiliation(s)
- Sara Liébana Viñas
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, 47057 Duisburg, Germany
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Li ZA, Fontaíña-Troitiño N, Kovács A, Liébana-Viñas S, Spasova M, Dunin-Borkowski RE, Müller M, Doennig D, Pentcheva R, Farle M, Salgueiriño V. Electrostatic doping as a source for robust ferromagnetism at the interface between antiferromagnetic cobalt oxides. Sci Rep 2015; 5:7997. [PMID: 25613569 PMCID: PMC4303864 DOI: 10.1038/srep07997] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 12/31/2014] [Indexed: 12/02/2022] Open
Abstract
Polar oxide interfaces are an important focus of research due to their novel functionality which is not available in the bulk constituents. So far, research has focused mainly on heterointerfaces derived from the perovskite structure. It is important to extend our understanding of electronic reconstruction phenomena to a broader class of materials and structure types. Here we report from high-resolution transmission electron microscopy and quantitative magnetometry a robust – above room temperature (Curie temperature TC ≫ 300 K) – environmentally stable- ferromagnetically coupled interface layer between the antiferromagnetic rocksalt CoO core and a 2–4 nm thick antiferromagnetic spinel Co3O4 surface layer in octahedron-shaped nanocrystals. Density functional theory calculations with an on-site Coulomb repulsion parameter identify the origin of the experimentally observed ferromagnetic phase as a charge transfer process (partial reduction) of Co3+ to Co2+ at the CoO/Co3O4 interface, with Co2+ being in the low spin state, unlike the high spin state of its counterpart in CoO. This finding may serve as a guideline for designing new functional nanomagnets based on oxidation resistant antiferromagnetic transition metal oxides.
Collapse
Affiliation(s)
- Zi-An Li
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen 48047, Duisburg (Germany)
| | | | - A Kovács
- Ernst Ruska-Centre and Peter Grünberg Institute, Research Centre Jülich, 52425 Jülich, (Germany)
| | - S Liébana-Viñas
- 1] Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen 48047, Duisburg (Germany) [2] Departamento de Física Aplicada, Universidade de Vigo 36310, Vigo (Spain)
| | - M Spasova
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen 48047, Duisburg (Germany)
| | - R E Dunin-Borkowski
- Ernst Ruska-Centre and Peter Grünberg Institute, Research Centre Jülich, 52425 Jülich, (Germany)
| | - M Müller
- Department of Earth and Environmental Sciences, Section Crystallography, LMU Munich, Theresienstr. 41, 80333 Munich (Germany)
| | - D Doennig
- Department of Earth and Environmental Sciences, Section Crystallography, LMU Munich, Theresienstr. 41, 80333 Munich (Germany)
| | - R Pentcheva
- 1] Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen 48047, Duisburg (Germany) [2] Department of Earth and Environmental Sciences, Section Crystallography, LMU Munich, Theresienstr. 41, 80333 Munich (Germany)
| | - M Farle
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen 48047, Duisburg (Germany)
| | - V Salgueiriño
- Departamento de Física Aplicada, Universidade de Vigo 36310, Vigo (Spain)
| |
Collapse
|
39
|
Rod I, Meckenstock R, Zähres H, Derricks C, Mushenok F, Reckers N, Kijamnajsuk P, Wiedwald U, Farle M. Bolometer detection of magnetic resonances in nanoscaled objects. Nanotechnology 2014; 25:425302. [PMID: 25271896 DOI: 10.1088/0957-4484/25/42/425302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report on a nanoscaled thermocouple (ThC) as a temperature sensor of a highly sensitive bolometer for probing the dissipative damping of spin dynamics in nanosized Permalloy (Py) stripes. The Au-Pd ThC based device is fabricated by standard electron beam lithography on a 200 nm silicon nitride membrane to minimize heat dissipation through the substrate. We show that this thermal sensor allows not only measurements of the temperature change on the order of a few mK due to the uniform resonant microwave (MW) absorption by the Py stripe but also detection of standing spin waves of different mode numbers. Using a 3D finite element method, we estimate the absorbed MW power by the stripe in resonance and prove the necessity of using substrates with an extremely low heat dissipation like a silicon nitride membrane for successful thermal detection. The voltage responsivity and the noise equivalent power for the ThC-based bolometer are equal to 15 V W(-1) and 3 nW Hz(-1/2), respectively. The ThC device offers a magnetic resonance response of 1 nV/(μ(B) W) corresponding to a sensitivity of 10(9) spins and a temperature resolution of 300 μK under vacuum conditions.
Collapse
Affiliation(s)
- Irina Rod
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Lotharstr. 1, D-47057 Duisburg, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Kamran MA, Liu R, Shi LJ, Li ZA, Marzi T, Schöppner C, Farle M, Zou B. Tunable emission properties by ferromagnetic coupling Mn(II) aggregates in Mn-doped CdS microbelts/nanowires. Nanotechnology 2014; 25:385201. [PMID: 25180542 DOI: 10.1088/0957-4484/25/38/385201] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Tunable optical emission properties from ferromagnetic semiconductors have not been well identified yet. In this work, high-quality Mn(II)-doped CdS nanowires and micrometer belts were prepared using a controlled chemical vapor deposition technique. The Mn doping could be controlled with time, precursor concentration and temperature. These wires or belts can produce both tunable redshifted emissions and ferromagnetic responses simultaneously upon doping. The strong emission bands at 572, 651, 693, 712, 745, 768, 787 and 803 nm, due to the Mn(II) (4)T1((4)G) → (6)A1((6)s) d-d transition, can be detected and accounted for by the aggregation of Mn ions at Cd sites in the CdS lattice at high temperature. These aggregates with ferromagnetism and shifted luminescence are related to the excitonic magnetic polaron (EMP) and localized EMP formations; this is verified by ab initio calculations. The correlation between aggregation-dependent optical emissions and ferromagnetic responses not only presents a new size effect for diluted magnetic semiconductors (DMSs), but also supplies a possible way to study or modulate the ferromagnetic properties of a DMS and to fabricate spin-related photonic devices in the future.
Collapse
Affiliation(s)
- Muhammad Arshad Kamran
- Beijing Key Laboratory of Nanophotonics & Ultrafine Optoelectronic Systems, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Angelakeris M, Li ZA, Sakellari D, Simeonidis K, Spasova M, Farle M. Can commercial ferrofluids be exploited in AC magnetic hyperthermia treatment to address diverse biomedical aspects? EPJ Web of Conferences 2014. [DOI: 10.1051/epjconf/20147508002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
42
|
Comesaña-Hermo M, Estivill R, Ciuculescu D, Li ZA, Spasova M, Farle M, Amiens C. Effect of a side reaction involving structural changes of the surfactants on the shape control of cobalt nanoparticles. Langmuir 2014; 30:4474-4482. [PMID: 24720393 DOI: 10.1021/la5005165] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Cobalt nanoparticles with different sizes and morphologies including spheres, rods, disks, and hexagonal prisms have been synthesized through the decomposition of the olefinic precursor [Co(η(3)-C8H13)(η(4)-C8H12)] under dihydrogen, in the presence of hexadecylamine and different rhodamine derivatives, or aromatic carboxylic acids. UV-vis spectroscopy, X-ray diffraction, low and high resolution transmission electron microscopy, and electron tomography have been used to characterize the nanomaterials. Especially, the Co nanodisks formed present characteristics that make them ideal nanocrystals for applications such as magnetic data storage. Focusing on their growth process, we have evidenced that a reaction between hexadecylamine and rhodamine B occurs during the formation of these Co nanodisks. This reaction limits the amount of free acid and amine, usually at the origin of the formation of single crystal Co rods and wires, in the growth medium of the nanocrystals. As a consequence, a growth mechanism based on the structure of the preformed seeds rather than oriented attachment or template assisted growth is postulated to explain the formation of the nanodisks.
Collapse
Affiliation(s)
- Miguel Comesaña-Hermo
- Laboratoire de Chimie de Coordination, CNRS , 205 route de Narbonne, F-31077 Toulouse, France
| | | | | | | | | | | | | |
Collapse
|
43
|
Fontaíña-Troitiño N, Liébana-Viñas S, Rodríguez-González B, Li ZA, Spasova M, Farle M, Salgueiriño V. Room-temperature ferromagnetism in antiferromagnetic cobalt oxide nanooctahedra. Nano Lett 2014; 14:640-7. [PMID: 24467516 DOI: 10.1021/nl4038533] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Cobalt oxide octahedra were synthesized by thermal decomposition. Each octahedron-shaped nanoparticle consists of an antiferromagnetic CoO core enclosed by eight {111} facets interfaced to a thin (∼ 4 nm) surface layer of strained Co3O4. The nearly perfectly octahedral shaped particles with 20, 40, and 85 nm edge length show a weak room-temperature ferromagnetism that can be attributed to ferromagnetic correlations appearing due to strained lattice configurations at the CoO/Co3O4 interface.
Collapse
|
44
|
Sun Z, Xie K, Li ZA, Sinev I, Ebbinghaus P, Erbe A, Farle M, Schuhmann W, Muhler M, Ventosa E. Hollow and Yolk-Shell Iron Oxide Nanostructures on Few-Layer Graphene in Li-Ion Batteries. Chemistry 2014; 20:2022-30. [DOI: 10.1002/chem.201303723] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Indexed: 11/07/2022]
|
45
|
Liu R, Li ZA, Zhang C, Wang X, Kamran MA, Farle M, Zou B. Single-step synthesis of monolithic comb-like CdS nanostructures with tunable waveguide properties. Nano Lett 2013; 13:2997-3001. [PMID: 23701186 DOI: 10.1021/nl401726z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Using a simple in situ seeding chemical vapor deposition (CVD) process, comb-like (branched) monolithic CdS micro/nanostructures were grown. Efficient optical coupling between the backbone and the teeth of the branched architecture is demonstrated by distributing light from an UV-laser-excited spot at one end of the backbone to all branch tips. By varying the deposition conditions, the orientation of the branches with respect to the backbone, their size and density can be tuned as well as the size of the backbone. This in situ seeding CVD method has the potential for a low-cost single-step fabrication of high-quality, micro/nanointegrated photonic devices, with tunable complex waveguiding possibilities.
Collapse
Affiliation(s)
- Ruibin Liu
- Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing 100081, China.
| | | | | | | | | | | | | |
Collapse
|
46
|
Sun Z, Masa J, Xia W, König D, Ludwig A, Li ZA, Farle M, Schuhmann W, Muhler M. Rapid and Surfactant-Free Synthesis of Bimetallic Pt–Cu Nanoparticles Simply via Ultrasound-Assisted Redox Replacement. ACS Catal 2012. [DOI: 10.1021/cs300187z] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | | | | | - Zi-An Li
- Fakultät für Physik
and CeNIDE, Universität Duisburg-Essen, Lotharstrasse 1, D-47057 Duisburg, Germany
| | - Michael Farle
- Fakultät für Physik
and CeNIDE, Universität Duisburg-Essen, Lotharstrasse 1, D-47057 Duisburg, Germany
| | | | | |
Collapse
|
47
|
Comesaña-Hermo M, Ciuculescu D, Li ZA, Stienen S, Spasova M, Farle M, Amiens C. Stable single domain Co nanodisks: synthesis, structure and magnetism. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm16751d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
48
|
Antoniak C, Friedenberger N, Trunova A, Meckenstock R, Kronast F, Fauth K, Farle M, Wende H. Intrinsic Magnetism and Collective Magnetic Properties of Size-Selected Nanoparticles. Nanoparticles from the Gasphase 2012. [DOI: 10.1007/978-3-642-28546-2_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
|
49
|
Comesaña-Hermo M, Estivill R, Ciuculescu D, Amiens C, Farle M, Batat P, Jonusauskas G, McClenaghan ND, Lecante P, Tardin C, Mazeres S. Photomodulation of the magnetisation of Co nanocrystals decorated with rhodamine B. Chemphyschem 2011; 12:2915-9. [PMID: 21976370 DOI: 10.1002/cphc.201100616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Indexed: 11/06/2022]
Affiliation(s)
- Miguel Comesaña-Hermo
- CNRS, LCC (Laboratoire de Chimie de Coordination), 205 route de Narbonne, 31077 Toulouse, France
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Antoniak C, Gruner ME, Spasova M, Trunova AV, Römer FM, Warland A, Krumme B, Fauth K, Sun S, Entel P, Farle M, Wende H. A guideline for atomistic design and understanding of ultrahard nanomagnets. Nat Commun 2011; 2:528. [DOI: 10.1038/ncomms1538] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Accepted: 10/06/2011] [Indexed: 11/09/2022] Open
|