2026 | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 | 2015 | 2014 | 2013 | 2012 | 2011 | 2010 | 2009 | 2008
Deciphering conduction mechanisms and microstructural properties in La0.8Sr0.1Ba0.1FeO3 compound: insights into charge carrier dynamics
Authors: Dhahri, H.; Moualhi, Y.; Eddine, M.S.; Omri, A.; Tozri, A.; Zaidi, N.; Rahmouni, H.; Costa, B.F.O.; Graça, M.P.F.
Ref.: Bull. Mater. Sci. 48(4), 142 (2025)
Abstract: This study provides new insights into the structure, morphology and conduction mechanisms of the La0.8Sr0.1Ba0.1FeO3 compound synthesized via the sol-gel method. A better understanding of its properties paves the way for potential applications in areas such as sensing, batteries and electrochemical devices. To examine the physical properties of the prepared sample, a variety of techniques, such as FTIR spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and impedance spectroscopy, were used. The XRD analysis confirmed that the prepared powder exhibits a single phase that correspond to the rhombohedral structure (with R3\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\overline{3}$$\end{document}c space group). The SEM images revealed a uniform nanometric granular morphology. The Raman spectroscopy evidenced the characteristic vibration modes of the perovskite structures. Complex impedance measurements as a function of frequency and temperature were carried out to confirm the strong correlation between the microstructure and the electrical response of the material. In the limit of the AC regime, the conductivity spectra of the compound were analyzed using Jonscher´s power law. The temperature dependence of the exponent suggests that the conductivity response at high frequencies is related to the activation of the overlapping large polaron tunneling (OLPT) and the correlated barrier hopping (CBH) conduction processes. The DC conductivity investigation indicates that La0.8Sr0.1Ba0.1FeO3 exhibits a semiconductor behaviour over a large temperature domain. This behaviour is related to the activation of the small polaron hopping (SPH) process at high temperatures, the greaves variable range hopping (VRH) process in the intermediate temperature range, and the Mott-VRH mechanism at low temperatures. The presence of relaxation phenomena is confirmed via variation of the imaginary part of the impedance spectra. Likewise, the Nyquist diagrams show the main importance of the microstructure on governing the electrical response of the ceramic compounds.
