Conductive, dielectric and magnetic properties of Y-substituted LaFeO3 ceramics

La1-xYxFeO3 (x = 0, 0.25, 0.5, 0.75, 1.0) ceramics have been prepared by a standard solid-state sintering process, and the conductive, dielectric and magnetic properties have been determined together with the structure. The bi-phase structure with Pbnm and P2(1)nm is determined for x = 0.5, and the Pbnm single phase is determined for all other compositions. The dielectric constant can be modified to vary in 3 orders of magnitude by Y-substitution as a result of the conductivity change. Two dielectric anomalies are found due to the increase of DC conductivity and semiconductor to metal phase transition in all La1-xYxFeO3 ceramics. The high temperature DC conductivity is dominated by long-range motion of double ionized oxygen vacancies. With increasing Y-substitution, the magnetic transition temperature drops gradually from 742 to 642 K due to the decrease of Fe-O-Fe bond angles. Weak ferromagnetic state has been observed by M-H hysteresis loops and magnetic domains from MFM phase images. Enhanced magnetic property with increased remnant magnetization is achieved by Y-substitution. (C) 2019 Elsevier B.V. All rights reserved.