Abstract
An investigation on single phase semiconducting polycrystalline Pr0.7Ca0.3MnO3 and Pr0.7Ca0.3MnCo0.1O3 crystallized in the orthorhombic system with Pnma space group is reported. We found that σDC increases when introducing Co for T<110K but for T>110K, it decreases. Also, the contribution of hopping process in conduction mechanism was in agreement with the Jonscher law and Mott theory. Capacitance was extensively dependent on temperature and frequency. A dielectric transition was observed at T=150K for the doped compound. The temperature dependence of dielectric permittivity is well described by Curie–Weiss law. The parameter of deviation from Curie–Weiss behavior to modified Curie–Weiss law is found to be ΔTm=30K. The substitution of Mn by Co was found to destroy the charge order state observed in the parent compound and to induce a ferromagnetic phase at low temperature. The cobalt-substituted sample exhibits a maximum value of magnetic entropy change |∆Smax|=3.2Jkg−1K−1and a large relative cooling power with a maximum value of 301J/kg under an applied field of 5T. Technically, these large values make the prepared material very promising for magnetic refrigeration.
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.
