Magnetocaloric effect in the ordered double perovskite Sr2FeMo1−xWxO6

The effects of B-site cations substitution and antisite (AS) defects on the Curie temperature (TC) and the magnetocaloric effect in the double perovskites Sr2FeMo1−xWxO6 (0≤x≤0.5) prepared by mechanical alloying have been investigated. With a small amount of W doping, not only the magnetization but also the magnetic entropy change (|ΔSM|) 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 TC. The maximum of the magnetic entropy change peaks at the TC obtained by the derivative method, and a large magnetic entropy change (∼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 .