Phase Separation of La0.70-xErxSr0.30MnO3 and its Effect on Magnetic and Magnetocaloric Properties

• Tipo: Artigo em Livro de Atas de Conferência Internacional
• Data: 2008

Autores

amaral, j. s. (Autor) Outra; reis, m. s. (Autor) Outra; araujo, j. p. (Autor) FCUP; mendonaca, t. m. (Autor) Outra; tavares, p. b. (Autor) Outra; amaral, v. s. (Autor) Outra; vieira, j. m. (Autor) Outra

Ata de Conferência Internacional

Título: Advanced Materials Forum IV

Páginas: 338-342

IV International Materials Symposium Materiais 2007 and XIII Encontro da Sociedade Portuguesa de Materiais

Porto, Portugal, April 1-4, 2007

Indexação

ISI Web of Knowledge - 2 Citações

Scopus - 2 Citações

Outras Informações

ID Authenticus: P-004-27X

Abstract (EN): Manganites of general formula ABMnO(3) (where A is a trivalent rare-earth ion and B is a divalent dopant) have interesting properties, namely colossal magnetoresistance and their applicability as materials for active magnetic regenerators. La0.70Sr0.30MnO3 (LSMO) is a ferromagnet presenting considerable magnetocaloric effect, with operating temperature T-C similar to 370 K and magnetic entropy variation comparable to pure Gadolinium. The high value of T-C makes LSMO unsuitable for room-temperature magnetic refrigeration applications, but by substituting. La With the high-magnetic moment ion Er, T-C is lowered and total magnetic entropy increases. We have found a limit of solid solubility of Er ions in LSMO, in samples prepared by either solid state or sot-gel techniques in previous works [1]. in accordance with other authors [2]. We now present a more detailed study of this limit of solubility. with more samples prepared with Er substitution close to the solubility limit and SEM microscopy clearly showing the changes in microstructure caused by the formation of a secondary ErMnO3 phase, in accordance with x-ray diffraction data and T-C variation along the series. The magnetocaloric properties of the series are also presented, showing the increase of Relative Cooling Power along the series, in applied magnetic fields up to 1 T.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 5