Magnetocaloric properties of Cd-substituted perovskite-type manganese oxides

Polycrystalline samples of cadmium-doped lanthanum manganites having nanometric crystallite size have been synthesized by sol–gel method. The Curie temperature (TC) of the prepared samples is found to be strongly dependent on Cd content and spans between 253 and 270 K. The Curie temperature has been analysed by two methods: a linear extrapolation of M(T) to zero magnetization and the thermodynamic model. Close to TC, a large change in magnetic entropy has been observed in all the samples. With increasing Cd concentration, a systematic increase in the values of magnetic entropy is observed (1.8≤ΔSmmax≤2.33 J/(kg K)) with H = 10 kOe. Our result about magnetocaloric properties suggests that La1 − xCdxMnO3 compounds are suitable for sub-room temperature magnetic refrigeration.