Magnetocaloric effect in the ordered double perovskite Sr2FeMo1-xWxO6

摘要

The effects of B-site cations substitution and antisite (AS) defects on the Curie temperature (T-C) and the magnetocaloric effect in the double perovskites Sr2FeMo1-xWxO6 (0less than or equal toxless than or equal to0.5) prepared by mechanical alloying have been investigated. With a small amount of W doping, not only the magnetization but also the magnetic entropy change (DeltaS(M)) have been enhanced. The Curie temperature has been analyzed by two methods: extrapolation and derivative. The experimental results indicate that TC decreases with increasing W substitution independently of the method used to obtain T-C. The maximum of the magnetic entropy change peaks at the T-C obtained by the derivative method, and a large magnetic entropy change (similar to 1.32 J/kg K) is obtained at 381 K in the sample Sr2FeMo1-xWxO6 (x = 0.35) by changing the applied magnetic field by 10 kOe. (C) 2004 Elsevier Ltd. All rights reserved.