Synthesis, Structural and Morphological Characterization, and Dielectrical Behavior of BaFeO_3-x

Abstract

This paper presents a comprehensive investigation on the synthesis, characterization, and dielectric properties of BaFeO_3-x material. The solid-state process was utilized, employing high-purity BaCO₃ and Fe₂O₃ precursors. The calcination step at different temperatures (800 °C, 900 °C, and 1000 °C) revealed that the sample calcined at 1000 °C exhibited the desired perovskite phase with no impurities. Morphological analysis through scanning electron microscopy (SEM) exhibited homogenous cubic grains with well-defined shapes and sizes. The sintered pellets at 1100 °C demonstrated excellent densification, devoid of visible pores or voids, and well-structured grain boundaries. The dielectric measurements unveiled intriguing properties of the BaFeO_3-x samples. The dielectric constant exhibited a remarkable peak value of 55,000 at the transition temperature of 145 °C, with an increasing trend as the frequency increased. The dielectric constant also demonstrated frequency-dependent behavior, with higher values at lower frequencies. The dielectric loss remained low below the transition temperature but increased beyond it. Additionally, the modified Uchino law was applied, revealing a linear fit between ln[(ε_max/ε_r)-1] and ln(T˗T_m) at 1 kHz, with a slope of γ (2.8721) and a characteristic length scale of δ (64.34). These findings provide insights into the temperature-dependent dielectric behavior of the material. This study highlights the significance of calcination temperature for achieving the desired crystal structure, as well as the importance of sintering in obtaining dense and well-structured pellets. The intriguing dielectric properties of BaFeO_3-x offer potential applications in electronics and energy storage.

Keywords:

• Perovskite
• X-ray diffraction
• SEM
• dielectric properties

Disclosure statement

No potential conflict of interest was reported by the author(s).