FePt icosahedra with magnetic cores and catalytic shells
Surprisingly oxidation resistant icosahedral FePt nanoparticles showing hard-magnetic properties have been fabricated by an inert-gas condensation method with in-flight annealing. High-resolution transmission electron microscopy (HRTEM) images with sub-Angstrom resolution of the nanoparticle have be...
| Autores principales: | , , , , , , , , |
|---|---|
| Formato: | Artículo |
| Lenguaje: | inglés |
| Publicado: |
American Chemical Society
2009
|
| Materias: | |
| Acceso en línea: | http://eprints.uanl.mx/8950/1/FePt%20Icosahedra%20with%20Magnetic%20Cores%20and%20Catalytic%20Shells.pdf |
| _version_ | 1824370876455321600 |
|---|---|
| author | Wang, Rongming Dmitrieva, Olga Farle, Michael Dumpich, Güntner Acet, Mehmet Mejía Rosales, Sergio Pérez Tijerina, Eduardo Yacamán, Miguel José Kisielowski, Christian |
| author_facet | Wang, Rongming Dmitrieva, Olga Farle, Michael Dumpich, Güntner Acet, Mehmet Mejía Rosales, Sergio Pérez Tijerina, Eduardo Yacamán, Miguel José Kisielowski, Christian |
| author_sort | Wang, Rongming |
| collection | Repositorio Institucional |
| description | Surprisingly oxidation resistant icosahedral FePt nanoparticles showing hard-magnetic properties have been fabricated by an inert-gas condensation method with in-flight annealing. High-resolution transmission electron microscopy (HRTEM) images with sub-Angstrom resolution of the nanoparticle have been obtained with focal series reconstruction, revealing noncrystalline nature of the nanoparticle. Digital dark-field method combined with structure reconstruction as well as HRTEM simulations reveal that these nanoparticles have icosahedral structure with shell periodicity. Localized lattice relaxations have been studied by extracting the position of individual atomic columns with a precision of about (0.002 nm. The lattice spacings of (111) planes from the surface region to the center of the icosahedra are found to decrease exponentially with shell numbers. Computational studies and energy-filtered transmission electron microscopy analyses suggest that a Pt-enriched surface layer is energetically favored and that site-specific vacancies are formed at the edges of facettes, which was experimentally observed. The presence of the Pt-enriched shell around an Fe/Pt core explains the environmental stability of the magnetic icosahedra and strongly reduces the exchange coupling between neighboring particles, thereby possibly providing the highest packing density for future magnetic storage media based on FePt nanoparticles. |
| format | Article |
| id | eprints-8950 |
| institution | UANL |
| language | English |
| publishDate | 2009 |
| publisher | American Chemical Society |
| record_format | eprints |
| spelling | eprints-89502016-02-08T21:38:46Z http://eprints.uanl.mx/8950/ FePt icosahedra with magnetic cores and catalytic shells Wang, Rongming Dmitrieva, Olga Farle, Michael Dumpich, Güntner Acet, Mehmet Mejía Rosales, Sergio Pérez Tijerina, Eduardo Yacamán, Miguel José Kisielowski, Christian Q Ciencias en General QC Física Surprisingly oxidation resistant icosahedral FePt nanoparticles showing hard-magnetic properties have been fabricated by an inert-gas condensation method with in-flight annealing. High-resolution transmission electron microscopy (HRTEM) images with sub-Angstrom resolution of the nanoparticle have been obtained with focal series reconstruction, revealing noncrystalline nature of the nanoparticle. Digital dark-field method combined with structure reconstruction as well as HRTEM simulations reveal that these nanoparticles have icosahedral structure with shell periodicity. Localized lattice relaxations have been studied by extracting the position of individual atomic columns with a precision of about (0.002 nm. The lattice spacings of (111) planes from the surface region to the center of the icosahedra are found to decrease exponentially with shell numbers. Computational studies and energy-filtered transmission electron microscopy analyses suggest that a Pt-enriched surface layer is energetically favored and that site-specific vacancies are formed at the edges of facettes, which was experimentally observed. The presence of the Pt-enriched shell around an Fe/Pt core explains the environmental stability of the magnetic icosahedra and strongly reduces the exchange coupling between neighboring particles, thereby possibly providing the highest packing density for future magnetic storage media based on FePt nanoparticles. American Chemical Society 2009 Article PeerReviewed text en cc_by_nc_nd http://eprints.uanl.mx/8950/1/FePt%20Icosahedra%20with%20Magnetic%20Cores%20and%20Catalytic%20Shells.pdf http://eprints.uanl.mx/8950/1.haspreviewThumbnailVersion/FePt%20Icosahedra%20with%20Magnetic%20Cores%20and%20Catalytic%20Shells.pdf Wang, Rongming y Dmitrieva, Olga y Farle, Michael y Dumpich, Güntner y Acet, Mehmet y Mejía Rosales, Sergio y Pérez Tijerina, Eduardo y Yacamán, Miguel José y Kisielowski, Christian (2009) FePt icosahedra with magnetic cores and catalytic shells. Journal of physical chemistry C, 113. pp. 4395-4400. ISSN 1256-1260 |
| spellingShingle | Q Ciencias en General QC Física Wang, Rongming Dmitrieva, Olga Farle, Michael Dumpich, Güntner Acet, Mehmet Mejía Rosales, Sergio Pérez Tijerina, Eduardo Yacamán, Miguel José Kisielowski, Christian FePt icosahedra with magnetic cores and catalytic shells |
| thumbnail | https://rediab.uanl.mx/themes/sandal5/images/online.png |
| title | FePt icosahedra with magnetic cores and catalytic shells |
| title_full | FePt icosahedra with magnetic cores and catalytic shells |
| title_fullStr | FePt icosahedra with magnetic cores and catalytic shells |
| title_full_unstemmed | FePt icosahedra with magnetic cores and catalytic shells |
| title_short | FePt icosahedra with magnetic cores and catalytic shells |
| title_sort | fept icosahedra with magnetic cores and catalytic shells |
| topic | Q Ciencias en General QC Física |
| url | http://eprints.uanl.mx/8950/1/FePt%20Icosahedra%20with%20Magnetic%20Cores%20and%20Catalytic%20Shells.pdf |
| work_keys_str_mv | AT wangrongming fepticosahedrawithmagneticcoresandcatalyticshells AT dmitrievaolga fepticosahedrawithmagneticcoresandcatalyticshells AT farlemichael fepticosahedrawithmagneticcoresandcatalyticshells AT dumpichguntner fepticosahedrawithmagneticcoresandcatalyticshells AT acetmehmet fepticosahedrawithmagneticcoresandcatalyticshells AT mejiarosalessergio fepticosahedrawithmagneticcoresandcatalyticshells AT pereztijerinaeduardo fepticosahedrawithmagneticcoresandcatalyticshells AT yacamanmigueljose fepticosahedrawithmagneticcoresandcatalyticshells AT kisielowskichristian fepticosahedrawithmagneticcoresandcatalyticshells |