Publicação: Intrinsic magnetic properties of BixCo2-xMnO 4 spinels obtained by short-time etching
Nenhuma Miniatura disponível
Data
2013-08-01
Orientador
Coorientador
Pós-graduação
Curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Editor
Tipo
Artigo
Direito de acesso
Acesso restrito
Resumo
We report the structural and magnetic properties of Co2MnO 4, partially substituted by Bi at the octahedral site. Bismuth enhances ferromagnetism due to a decrease of the Co2+-Co2+ antiferromagnetic interactions and an increase of the Mn3+-Mn 4+ exchanges. Spurious phases (magnetic and/or nonmagnetic oxides) can easily form because of the large differences between the ionic radii of Bi3+ and Co3+, hiding or altering the intrinsic physical properties of the main BixCo2-xMnO4 phase. An easy way to eliminate the secondary phases is using acid reagents. Short-time etching of Bi0.1Co1.9MnO4 using nitric acid was successfully used, keeping most of the properties of the initial compound, with no alteration of the crystallographic structure. Final stoichiometry was respected (∼Bi0.08Co1.82MnO4), meaning that the material after etching definitely contains bismuth elements in its structure and the observed properties are intrinsic to the oxide spinel. Additional experiments were performed as a function of the synthesis conditions, showing that an optimal pH value of 7 allowed the best magnetic response of the non-doped material. © 2013 Elsevier B.V. All rights reserved.
Descrição
Palavras-chave
Etching, Ferrimagnetism, Multiferroics, Oxide spinel, pH, Additional experiments, Antiferro-magnetic interactions, Crystallographic structure, Magnetic response, Oxide spinels, Structural and magnetic properties, Synthesis conditions, Bismuth, Bismuth compounds, Carbon dioxide, Magnetic properties, Manganese, Manganese oxide, Stoichiometry, Cobalt compounds
Idioma
Inglês
Como citar
Journal of Magnetism and Magnetic Materials, v. 339, p. 157-162.
