Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures
Magnetic core–shell nanostructures offer a viable solution for tunable magnetism via nanoscale exchange interactions in a single-component unit. A typical synthetic approach for monodisperse bimagnetic ferrite core–shell nanostructures employs the seed-mediated growth method using the heating-up pro...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2021
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10356/151306 |
| _version_ | 1826117531162640384 |
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| author | Lee, Kwan Lee, Sangyeob Ahn, Byungmin |
| author2 | School of Electrical and Electronic Engineering |
| author_facet | School of Electrical and Electronic Engineering Lee, Kwan Lee, Sangyeob Ahn, Byungmin |
| author_sort | Lee, Kwan |
| collection | NTU |
| description | Magnetic core–shell nanostructures offer a viable solution for tunable magnetism via nanoscale exchange interactions in a single-component unit. A typical synthetic approach for monodisperse bimagnetic ferrite core–shell nanostructures employs the seed-mediated growth method using the heating-up process. Understanding magnetic core–shell interface formation and their interactions is crucial; however, the magnetical persistence of the pristine core component during the heating-up process is unclear. Here, we elucidate the enhancement mechanism of magnetic anisotropy when the hard–soft core–shell nanostructures are formed with the ultrathin shell layer. The heating-up effect on the core component exhibits the coordination change of ligand chemisorption with surface metal ions, which leads to a substantial increase in surface anisotropy due to enhanced spin–orbit couplings. We further demonstrate that the selection of metal precursors and surfactants for additional shell layer formation is important. The kinetic of the shell formation rate by their thermolysis and atomic-scale surface etching by the surfactant led to the disordering of surface spins on the core parts. Our observations provide the underlying mechanism of high anisotropic magnetism while bimagnetic ferrite core–shell interface formation and the voyage of synthetic procedures for the additional shell layer are critical to an outcoming magnetism. |
| first_indexed | 2024-10-01T04:29:07Z |
| format | Journal Article |
| id | ntu-10356/151306 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T04:29:07Z |
| publishDate | 2021 |
| record_format | dspace |
| spelling | ntu-10356/1513062021-07-06T01:39:37Z Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures Lee, Kwan Lee, Sangyeob Ahn, Byungmin School of Electrical and Electronic Engineering Engineering::Materials Nanocubes Metals Magnetic core–shell nanostructures offer a viable solution for tunable magnetism via nanoscale exchange interactions in a single-component unit. A typical synthetic approach for monodisperse bimagnetic ferrite core–shell nanostructures employs the seed-mediated growth method using the heating-up process. Understanding magnetic core–shell interface formation and their interactions is crucial; however, the magnetical persistence of the pristine core component during the heating-up process is unclear. Here, we elucidate the enhancement mechanism of magnetic anisotropy when the hard–soft core–shell nanostructures are formed with the ultrathin shell layer. The heating-up effect on the core component exhibits the coordination change of ligand chemisorption with surface metal ions, which leads to a substantial increase in surface anisotropy due to enhanced spin–orbit couplings. We further demonstrate that the selection of metal precursors and surfactants for additional shell layer formation is important. The kinetic of the shell formation rate by their thermolysis and atomic-scale surface etching by the surfactant led to the disordering of surface spins on the core parts. Our observations provide the underlying mechanism of high anisotropic magnetism while bimagnetic ferrite core–shell interface formation and the voyage of synthetic procedures for the additional shell layer are critical to an outcoming magnetism. This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF2018R1D1A1B07044481). 2021-07-06T01:39:37Z 2021-07-06T01:39:37Z 2019 Journal Article Lee, K., Lee, S. & Ahn, B. (2019). Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures. Chemistry of Materials, 31(3), 728-736. https://dx.doi.org/10.1021/acs.chemmater.8b03591 0897-4756 0000-0002-8269-6579 0000-0002-9957-990X 0000-0002-0866-6398 https://hdl.handle.net/10356/151306 10.1021/acs.chemmater.8b03591 2-s2.0-85061649263 3 31 728 736 en Chemistry of Materials © 2019 American Chemical Society. All rights reserved. |
| spellingShingle | Engineering::Materials Nanocubes Metals Lee, Kwan Lee, Sangyeob Ahn, Byungmin Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures |
| title | Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures |
| title_full | Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures |
| title_fullStr | Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures |
| title_full_unstemmed | Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures |
| title_short | Understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard–soft core–shell nanostructures |
| title_sort | understanding high anisotropic magnetism by ultrathin shell layer formation for magnetically hard soft core shell nanostructures |
| topic | Engineering::Materials Nanocubes Metals |
| url | https://hdl.handle.net/10356/151306 |
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