Investigating Fe-doped Ba0.67Ni0.33Mn1−xFexO3 (x = 0, 0.2) ceramics: insights into electrical and dielectric behaviors

Abstract

This study investigates the characteristics of the Ba_0.67Ni_0.33Mn_1−xFe_xO₃ perovskite compound, focusing on its structural and electrical aspects under varying Fe doping levels at the Mn-site (x = 0, 0.2). X-ray diffraction patterns confirm the material's consistent structure, with Fe³⁺ ions substituting Mn³⁺ ions while maintaining their identical ionic radius. Nano-crystallinity studies reveal single-phase crystallization in the orthorhombic structure with space group Imma. Samples are prepared through conventional solid-state sintering. The Williamson–Hall method calculates crystallite sizes, averaging 37 nm for x = 0 and 33 nm for x = 0.2. Electrical properties are examined using complex impedance spectroscopy at different temperatures and frequencies. Techniques such as energy dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM) assess chemical composition. Activation energy values increase from 0.138 eV for x = 0 to 0.171 eV for x = 0.2, leading to reduced dc conductivity across the investigated temperature range. Dielectric permittivity enhances proportionally with increasing Fe doping. Variations in impedance profiles reveal a relaxation phenomenon. A circuit model, R_g + (R_gb//CPE_gb), elucidates impedance data. This study illuminates the interplay between Fe doping, activation energy, and electrical conductivity in Ba_0.67Ni_0.33Mn_1−xFe_xO₃ perovskite, offering insights applicable to electronic and energy-related devices. Perovskite-based nanomaterials have diverse environmental applications, including solar cells, light-emitting devices, transistors, sensors, and energy storage.