Abstract
The perovskite-type La0.5Ca0.5−xNaxMnO3 (0.05≤x≤0.2) ceramic samples were prepared using the solid-state reaction at high temperature. The X-ray powder diffraction refinement by means of the Rietveld technique reveals that all our samples are single phase and crystallize in the orthorhombic structure with Pbnm space group. Lattice parameters and unit cell volume are found to increase with increasing the average A-site ionic radius 〈rA〉. The substitution of calcium by monovalent element (Na) in La0.5Ca0.5MnO3 drives the system from a charge ordering state to a ferromagnetic behaviors observed near room temperature for all our substituted compounds with a Curie temperature TC slightly decreasing from 297 K for x=0.05 to 278 K for x=0.2. Magnetic entropy change |ΔSM|, deduced from magnetization measurements versus magnetic applied field at several temperatures, shifts to higher values with increasing Na content and reaches 1.14 J/kg K and 3.1 J/kg K for La0.5Ca0.3Na0.2MnO3 under magnetic applied field of 2 T and 7 T respectively.
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.
