Temperature-Induced Transition from Capacitive to Inductive Response in a High-Entropy Perovskite Oxide

A lanthanum-based high-entropy perovskite oxide, La(Fe0.2Ni0.2Ti0.2Co0.2Mn0.2)O3, was synthesized by high-energy ball milling followed by sintering. Rietveld refinement of the X-ray diffraction revealed a triclinic single-phase perovskite stabilized by high configurational entropy at the B-site. Impedance spectroscopy between 30 °C and 500 °C revealed a temperature-induced transition from capacitive to inductive-like behavior, attributed to thermally activated charge dynamics and interfacial polarization. Scanning Electron Microscopy and Energy-Dispersive X-ray Spectroscopy confirmed dense microstructures with uniform, equimolar cation distribution. These results establish a clear correlation between structural disorder and electrodynamic response in high-entropy oxides, highlighting their potential for thermally tunable dielectric devices.