Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets

In this work, we demonstrate that the reduction of the local internal stress by a low-temperature solvent-mediated thermal treatment is an effective post-treatment tool for magnetic hardening of chemically synthesized nanoparticles. As a case study, we used nonstoichiometric cobalt ferrite particles...

Descripción completa

Detalles Bibliográficos
Autores: Muzzi, Beatrice, Lottini, Elisabetta, Yaacoub, Nader, Peddis, Davide, Bertoni, Giovanni, Julián Fernández, César de, Sangregorio, Claudio, López Ortega, Alberto
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2022
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/45177
Acceso en línea:https://hdl.handle.net/2454/45177
Access Level:acceso abierto
Palabra clave:Cobalt ferrite
Coercivity
Geometrical phase analysis
Magnetic nanoparticles
Microstrain
Solvent-mediated annealing
id ES_08fda50bee79c7eeb479e1ea9962ce25
oai_identifier_str oai:academica-e.unavarra.es:2454/45177
network_acronym_str ES
network_name_str España
repository_id_str
spelling Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnetsMuzzi, BeatriceLottini, ElisabettaYaacoub, NaderPeddis, DavideBertoni, GiovanniJulián Fernández, César deSangregorio, ClaudioLópez Ortega, AlbertoCobalt ferriteCoercivityGeometrical phase analysisMagnetic nanoparticlesMicrostrainSolvent-mediated annealingIn this work, we demonstrate that the reduction of the local internal stress by a low-temperature solvent-mediated thermal treatment is an effective post-treatment tool for magnetic hardening of chemically synthesized nanoparticles. As a case study, we used nonstoichiometric cobalt ferrite particles of an average size of 32(8) nm synthesized by thermal decomposition, which were further subjected to solvent-mediated annealing at variable temperatures between 150 and 320 °C in an inert atmosphere. The postsynthesis treatment produces a 50% increase of the coercive field, without affecting neither the remanence ratio nor the spontaneous magnetization. As a consequence, the energy product and the magnetic energy storage capability, key features for applications as permanent magnets and magnetic hyperthermia, can be increased by ca. 70%. A deep structural, morphological, chemical, and magnetic characterization reveals that the mechanism governing the coercive field improvement is the reduction of the concomitant internal stresses induced by the low-temperature annealing postsynthesis treatment. Furthermore, we show that the medium where the mild annealing process occurs is essential to control the final properties of the nanoparticles because the classical annealing procedure (T > 350 °C) performed on a dried powder does not allow the release of the lattice stress, leading to the reduction of the initial coercive field. The strategy here proposed, therefore, constitutes a method to improve the magnetic properties of nanoparticles, which can be particularly appealing for those materials, as is the case of cobalt ferrite, currently investigated as building blocks for the development of rare-earth free permanent magnets.This work was supported by EU-H2020 AMPHIBIAN Project (Grant no. 720853). A.L.O. acknowledges support from the Universidad Pública de Navarra (Grant no. PJUPNA2020). Open access funding provided by Universidad Pública de Navarra.American Chemical SocietyCienciasZientziakInstitute for Advanced Materials and Mathematics - INAMAT2Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa2022info:eu-repo/semantics/articleinfo:eu-repo/semantics/acceptedVersionapplication/pdfhttps://hdl.handle.net/2454/45177reponame:Academica-e. Repositorio Institucional de la Universidad Pública de Navarrainstname:Universidad Pública de NavarraInglésCreative Commons Attribution 4.0 International (CC BY 4.0)https://creativecommons.org/licenses/by/4.0/info:eu-repo/semantics/openAccessoai:academica-e.unavarra.es:2454/451772026-06-17T12:41:47Z
dc.title.none.fl_str_mv Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets
title Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets
spellingShingle Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets
Muzzi, Beatrice
Cobalt ferrite
Coercivity
Geometrical phase analysis
Magnetic nanoparticles
Microstrain
Solvent-mediated annealing
title_short Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets
title_full Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets
title_fullStr Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets
title_full_unstemmed Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets
title_sort Hardening of cobalt ferrite nanoparticles by local crystal strain release: implications for rare earth free magnets
dc.creator.none.fl_str_mv Muzzi, Beatrice
Lottini, Elisabetta
Yaacoub, Nader
Peddis, Davide
Bertoni, Giovanni
Julián Fernández, César de
Sangregorio, Claudio
López Ortega, Alberto
author Muzzi, Beatrice
author_facet Muzzi, Beatrice
Lottini, Elisabetta
Yaacoub, Nader
Peddis, Davide
Bertoni, Giovanni
Julián Fernández, César de
Sangregorio, Claudio
López Ortega, Alberto
author_role author
author2 Lottini, Elisabetta
Yaacoub, Nader
Peddis, Davide
Bertoni, Giovanni
Julián Fernández, César de
Sangregorio, Claudio
López Ortega, Alberto
author2_role author
author
author
author
author
author
author
dc.contributor.none.fl_str_mv Ciencias
Zientziak
Institute for Advanced Materials and Mathematics - INAMAT2
Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
dc.subject.none.fl_str_mv Cobalt ferrite
Coercivity
Geometrical phase analysis
Magnetic nanoparticles
Microstrain
Solvent-mediated annealing
topic Cobalt ferrite
Coercivity
Geometrical phase analysis
Magnetic nanoparticles
Microstrain
Solvent-mediated annealing
description In this work, we demonstrate that the reduction of the local internal stress by a low-temperature solvent-mediated thermal treatment is an effective post-treatment tool for magnetic hardening of chemically synthesized nanoparticles. As a case study, we used nonstoichiometric cobalt ferrite particles of an average size of 32(8) nm synthesized by thermal decomposition, which were further subjected to solvent-mediated annealing at variable temperatures between 150 and 320 °C in an inert atmosphere. The postsynthesis treatment produces a 50% increase of the coercive field, without affecting neither the remanence ratio nor the spontaneous magnetization. As a consequence, the energy product and the magnetic energy storage capability, key features for applications as permanent magnets and magnetic hyperthermia, can be increased by ca. 70%. A deep structural, morphological, chemical, and magnetic characterization reveals that the mechanism governing the coercive field improvement is the reduction of the concomitant internal stresses induced by the low-temperature annealing postsynthesis treatment. Furthermore, we show that the medium where the mild annealing process occurs is essential to control the final properties of the nanoparticles because the classical annealing procedure (T > 350 °C) performed on a dried powder does not allow the release of the lattice stress, leading to the reduction of the initial coercive field. The strategy here proposed, therefore, constitutes a method to improve the magnetic properties of nanoparticles, which can be particularly appealing for those materials, as is the case of cobalt ferrite, currently investigated as building blocks for the development of rare-earth free permanent magnets.
publishDate 2022
dc.date.none.fl_str_mv 2022
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/acceptedVersion
format article
status_str acceptedVersion
dc.identifier.none.fl_str_mv https://hdl.handle.net/2454/45177
url https://hdl.handle.net/2454/45177
dc.language.none.fl_str_mv Inglés
language_invalid_str_mv Inglés
dc.rights.none.fl_str_mv Creative Commons Attribution 4.0 International (CC BY 4.0)
https://creativecommons.org/licenses/by/4.0/
info:eu-repo/semantics/openAccess
rights_invalid_str_mv Creative Commons Attribution 4.0 International (CC BY 4.0)
https://creativecommons.org/licenses/by/4.0/
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv American Chemical Society
publisher.none.fl_str_mv American Chemical Society
dc.source.none.fl_str_mv reponame:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
instname:Universidad Pública de Navarra
instname_str Universidad Pública de Navarra
reponame_str Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
collection Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
repository.name.fl_str_mv
repository.mail.fl_str_mv
_version_ 1869403080223621120
score 15.812429

Similares en LA Referencia