Understanding the Dependence of Nanoparticles Magnetothermal Properties on Their Size for Hyperthermia Applications: A Case Study for La-Sr Manganites

Autor(es):Mostrar menos -

Ferreira, Mylla C. ^[1] ; Pimentel, Bruno ^[1] ; Andrade, Vivian ^{[2, 3]} ; Zverev, Vladimir ^[4] ; Gimaev, Radel R. ^[4] ; Pomorov, Andrei S. ^[4] ; Pyatakov, Alexander ^[4] ; Alekhina, Yulia ^[4] ; Komlev, Aleksei ^[4] ; Makarova, Liudmila ^[4] ; Perov, Nikolai ^[4] ; Reis, Mario S. ^[1]

Afiliação do(s) autor(es)

^[1] Fluminense Fed Univ, Inst Phys, BR-24210346 Niteroi, RJ - Brazil

^[2] Univ Estadual Campinas, Gleb Wataghin Phys Inst, BR-13083859 Campinas, SP - Brazil

^[3] Univ Porto, IFIMUP Inst Phys Adv Mat Nanotechnol & Photon, P-4169007 Porto - Portugal

^[4] Moscow MV Lomonosov State Univ, Fac Phys, Moscow 119991 - Russia

• Tipo de documento: Artigo Científico
• Fonte: NANOMATERIALS; v. 11, n. 7 JUL 2021.
• Citações Web of Science: 0

Resumo

Magnetic oxides are promising materials for alternative health diagnoses and treatments. The aim of this work is to understand the dependence of the heating power with the nanoparticle (NP) mean size, for the manganite composition La0.75Sr0.25MnO3 (LSMO)-the one with maximum critical temperature for the whole La/Sr ratio of the series. We have prepared four different samples, each one annealed at different temperatures, in order to produce different mean NP sizes, ranging from 26 nm up to 106 nm. Magnetization measurements revealed a FC-ZFC irreversibility and from the coercive field as function of temperature we determined the blocking temperature. A phase diagram was delivered as a function of the NP mean size and, based on this, the heating mechanism understood. Small NPs (26 nm) is heated up within the paramagnetic range of temperature (T>T-c), and therefore provide low heating efficiency; while bigger NPs are heated up, from room temperature, within the magnetically blocked range of temperature (T<T-B), and also provide a small heating efficiency. The main finding of this article is related with the heating process for NPs within the magnetically unblocked range of temperature (T-c>T>TB), for intermediate mean diameter size of 37 nm, with maximum efficiency of heat transfer. (AU)

• Processo FAPESP: 17/10581-1 - Fenômenos emergentes em sistemas de dimensões reduzidas
• Beneficiário: Pascoal Jose Giglio Pagliuso
• Modalidade de apoio: Auxílio à Pesquisa - Projetos Especiais