Large magnetocaloric effect in Ti-modified La0.70Sr0.30MnO3 perovskite

The effect of Ti substitution on the magnetocaloric effect of the La0.70Sr0.30MnO3 perovskite was investigated. The magnetic entropy change (-Delta S-M) was deduced by two methods: a Maxwell relation and the Landau theory. The magnetocaloric data displays a large value of the magnetic entropy change (-Delta S-M) near the Curie temperature (T-C = 210 K), which increases when increasing the applied magnetic field. A good agreement is found between the experimental (-Delta S-M) and the one estimated by Landau theory. The relative cooling power values vary from 49 to 288 J kg(-1) upon variation of the applied magnetic field at 1 and 5 T. Under 5 T, the relative cooling power value for La0.70Sr0.30Mn0.90Ti0.10O3 is about 70% of the conventional refrigerant Gd material. As a result, the herein reported compound can be considered as a promising material in magnetic refrigeration technology. (C) 2010 Elsevier B.V. All rights reserved.