Abstract
In this work, we have investigated the magnetic properties and the magnetocaloric effect of La0.7−xNaxCa0.3MnO3 compounds, which were prepared by a conventional solid-state reaction technique. The Rietveld refinement results suggested that the samples are single phase belonging to an orthorhombic structure (space group Pnma). Analyzing temperature dependence of magnetization M(T) revealed that the Curie temperature (TC) increases with increasing Na content (x). Their TC value is found to be 260–298K for x=0.0–0.1, respectively. Base on M(T) data measured at different applied magnetic fields (H), temperature dependence of magnetic entropy change ΔSm(T) data for all the samples was calculated by using a phenomenological model. In the vicinity of TC, -ΔSm(T) curve reaches a maximum value (denoted as |ΔSmax|), which gradually increases with increasing H. Under 12kOe, the value of |ΔSmax| is in a range of 1.47–5.19J/kgK corresponding to the relative cooling power RCP=57.12–75.88J/kg. Applied the universal master curve method for the magnetic entropy change, we concluded that Na-doped in La0.7−xNaxCa0.3MnO3 compounds leads to modification the nature of the magnetic phase transition from the first- to the second-order.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
