Phase Separation of La0.70-xErxSr0.30MnO3 and its Effect on Magnetic and Magnetocaloric Properties
authors Amaral, JS; Reis, MS; Araujo, JP; Mendonaca, TM; Tavares, PB; Amaral, VS; Vieira, JM
editors Marques, AT; Silva, AF; Baptista, APM; Sa, C; Alves, FJLA; Malheiros, LF; Vieira, M
nationality International
journal ADVANCED MATERIALS FORUM IV
author keywords Manganites; Phase Transitions; Magnetocaloric Effect; Magnetic Refrigeration
keywords LA-SR MANGANITES; ER
abstract 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.
publisher TRANS TECH PUBLICATIONS LTD
issn 0255-5476
year published 2008
volume 587-588
beginning page 338
ending page +
web of science category Engineering, Multidisciplinary; Materials Science, Multidisciplinary
subject category Engineering; Materials Science
unique article identifier WOS:000259898200068

Apoio

1suponsers_list_ciceco.jpg