Effect of Ti-substitution on magnetic and magnetocaloric properties of La0.57Nd0.1Pb0.33MnO3

We have studied the effect of Ti substitution on magnetic and magnetocaloric properties in La0.57Nd0.1Pb0.33Mn1−xTixO3 (x = 0.1 and x = 0.15) over a wide temperature range (T = 240–340 K). The prepared samples remain single phase and exhibit paramagnetic (PM)–ferromagnetic (FM) phase transition (TC) at 300 and 280 K for x = 0.1 and x = 0.15, respectively. From the magnetic measurements as function of temperature and magnetic applied field, we have discovered a large magnetic entropy change (−ΔSM) at Curie temperature.ΔSM has been deduced by two methods: Maxwell relation and Landau theory. The maximum value of the magnetic entropy change obtained from the M(H) curves and it increases with increase of Ti content from 4.85 J kg−1 K−1 at 299 K to 5.2 J kg−1 K−1 at 279 K, under ΔH = 5 T. The field dependence of the magnetic entropy change is also analyzed showing the power law dependence, ΔS M ∝ Hn where n = 0.610(3) for x = 0.1 and n = 0.525(5) for x = 0.15 at their respective transition temperatures. The relative cooling power (RCP) and its field dependence are also analyzed. The obtained results show that La0.57Nd0.1Pb0.33Mn1−xTixO3 could be considered as a potential candidate for magnetic refrigeration applications around room temperature.

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► The prepared samples remain single phase and exhibit paramagnetic (PM)–ferromagnetic (FM) phase transition (TC) at 300 and 280 K.
► The maximum value of the magnetic entropy change obtained from the M(H) curves and it increases with increase of Ti content from 4.85 J kg−1 K−1 at 299 K to 5.2 J kg−1 K−1 at 279 K, under ΔH = 5 T.
► The field dependence of the magnetic entropy change is also analyzed showing the power law dependence, ΔSMα″ where n = 0.610(3) for x = 0.1 and n = 0.525(5) for x = 0.15 at their respective transition temperatures.