Effects of Mn-site doping on the magnetocaloric properties of La0.62Bi0.05Ca0.33Mn1-xRuxO3 manganite system

Abstract

This study reports the effects of Ru element doping in La0.62Bi0.05Ca0.33Mn1-xRuxO3 (x=0.0, 0.1 and 0.2) manganite compounds on the magnetocaloric (MC) properties of materials obtained by solid-state method. XRD analysis showed that the samples crystallized in orthorhombic structure (with Pnma space group). The magnetic phase transition temperatures of the samples were determined from the thermomagnetic curves as 221 K for x = 0.0 sample and 215 and 206 K for x = 0.1 and x = 0.2 samples, respectively, under 100 Oe applied field. Arrott plots confirm that the type of magnetic phase transition is second-order phase transition. The -∆S_M^max values were calculated as 7.55, 3.51 and 2.69 J/kgK for x = 0.0, 0.1 and 0.2 samples, respectively. Relative cooling power (RCP) values decrease with Ru doping. It was concluded that the Ru additive had an effect on reducing the transition temperatures and magnetic entropy change values of the samples.

Keywords

• magnetic entropy change
• magnetocaloric effect
• magnetic refrigeration
• perovskites.
• manyetik entropi değişimi
• manyetokalorik etki
• manyetik soğutma
• perovskitler.