Effect of B site partial Ru substitution on structural magnetic and magnetocaloric properties in La0.7Pb0.3Mn1-xRuxO3 (x=0.0, 0.1 and 0.2) perovskite system

Abstract

The La0.7Pb0.3Mn1-xRuxO3 (x = 0.0, 0.1 and 0.2) perovskite manganite compounds have been fabricated by solid-state reaction method to investigate structural, magnetic and magnetocaloric properties. All samples are indexed in the Rhombohedral structure with R (3) over tildec space group by using the Rietveld refinement method. The Curie temperature decreases from 336 K to 313 K when Ru (x = 0.1) is added to the structure and it becomes 335 K for x = 0.2. Maximum magnetic entropy change and relative cooling power values were calculated as 3.17, 3.15, 3.06 J kg(-1) K-1 for 5 T magnetic field change and 214.40, 160.20, 128.38 J kg(-1) under 4 T magnetic field change for x = 0.0, 0.1 and 0.2 in La0.7Pb0.3Mn1-xRuxO3, respectively. From the H/M vs M-2 plots obtained from isothermal magnetization curves, it is found that all samples exhibit a second-order magnetic phase transition, which shows reversible magnetocaloric effect. Under the light of all observed results, La0.7Pb0.3Mn1-xRuxO3 (x = 0.0, 0.1 and 0.2) perovskite manganite compounds can be considered as candidate materials above room temperature range magnetic cooling systems. (C) 2019 Elsevier B.V. All rights reserved.