Deciphering driven phase transitions: a study on the dielectric and electrical properties of Ca2Fe2O5

This study aims to contribute to the investigation of the electrical and dielectric behavior of the well-known brownmillerites Ca2Fe2O5 compound. The compound was produced using a solid-state reaction process and examined using X-ray powder diffraction and Rietveld refinement to confirm its orthorhombic crystal structure, as well as its cell characteristics. A thorough dielectric and electrical examination was carried out across a wide range of temperature and frequency, from 30 to 400 °C and 10 Hz to 1 MHz. Remarkably, at a relatively temperature of approximately 170 °C, the dielectric measurements revealed a complex behavior, indicative of diffuse phase transition. Similar distinctive changes were also observed in impedance spectroscopy and conductivity studies, suggesting a temperature like phase transition phenomenon. This observation was further substantiated through a differential scanning calorimetry analysis, which identified an endothermic dip at around 170 °C, signifying a structural disturbance at these temperatures. These findings contribute significantly to our comprehensive understanding of the material’s behavior across a wide temperature range, providing valuable insights into the polarization mechanisms, relaxation dynamics, and electrical conduction properties. Graphical abstract