S. Sahoo, K. Andryushin, P. K. Mahapatra, R. Choudhary
{"title":"Colossal dielectric response and complex impedance analysis of LaFeO3 ceramics","authors":"S. Sahoo, K. Andryushin, P. K. Mahapatra, R. Choudhary","doi":"10.1142/s2010135x22500199","DOIUrl":null,"url":null,"abstract":"The present investigations mainly focused on the colossal dielectric response and complex impedance analysis of LaFeO3 ceramics. The studied sample was prepared by a citrate gel method. Structural and microstructural properties are analyzed from the XRD pattern and SEM micrograph. The anomalies in the dielectric constant versus temperature plots are analyzed on the basis of polarization induced by the Maxwell-Wagner mechanisms and ferromagnetic interaction between the Fe[Formula: see text] ions driven by the oxygen vacancy mediated Fe[Formula: see text]–V[Formula: see text] –Fe[Formula: see text] exchange interaction A giant dielectric permittivity in the order of [Formula: see text]105 was observed in the sample even at the room temperature for 100 Hz. The colossal dielectric constant in LaFeO3 is mainly driven by the internal barrier layer capacitor (IBLC) formation. The formation of IBLC was explained on the basis of highly insulating grain boundary and less resistive/semiconducting grain, which was confirmed from both the resistance and capacitance of grain and grain boundary from the impedance analysis. The non-Debye-type relaxation process associated with the grain and grain boundary effect was investigated from the broad and asymmetric relaxation peak. The relaxation time for both the grain and grain boundary effect was also calculated. In addition to this, we have also analyzed the normalized bode plot of imaginary part of impedance and electrical modulus which suggests the relaxation process dominated by the short-range movement of charge carriers.","PeriodicalId":14871,"journal":{"name":"Journal of Advanced Dielectrics","volume":null,"pages":null},"PeriodicalIF":2.1000,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Advanced Dielectrics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1142/s2010135x22500199","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
The present investigations mainly focused on the colossal dielectric response and complex impedance analysis of LaFeO3 ceramics. The studied sample was prepared by a citrate gel method. Structural and microstructural properties are analyzed from the XRD pattern and SEM micrograph. The anomalies in the dielectric constant versus temperature plots are analyzed on the basis of polarization induced by the Maxwell-Wagner mechanisms and ferromagnetic interaction between the Fe[Formula: see text] ions driven by the oxygen vacancy mediated Fe[Formula: see text]–V[Formula: see text] –Fe[Formula: see text] exchange interaction A giant dielectric permittivity in the order of [Formula: see text]105 was observed in the sample even at the room temperature for 100 Hz. The colossal dielectric constant in LaFeO3 is mainly driven by the internal barrier layer capacitor (IBLC) formation. The formation of IBLC was explained on the basis of highly insulating grain boundary and less resistive/semiconducting grain, which was confirmed from both the resistance and capacitance of grain and grain boundary from the impedance analysis. The non-Debye-type relaxation process associated with the grain and grain boundary effect was investigated from the broad and asymmetric relaxation peak. The relaxation time for both the grain and grain boundary effect was also calculated. In addition to this, we have also analyzed the normalized bode plot of imaginary part of impedance and electrical modulus which suggests the relaxation process dominated by the short-range movement of charge carriers.
期刊介绍:
The Journal of Advanced Dielectrics is an international peer-reviewed journal for original contributions on the understanding and applications of dielectrics in modern electronic devices and systems. The journal seeks to provide an interdisciplinary forum for the rapid communication of novel research of high quality in, but not limited to, the following topics: Fundamentals of dielectrics (ab initio or first-principles calculations, density functional theory, phenomenological approaches). Polarization and related phenomena (spontaneous polarization, domain structure, polarization reversal). Dielectric relaxation (universal relaxation law, relaxor ferroelectrics, giant permittivity, flexoelectric effect). Ferroelectric materials and devices (single crystals and ceramics). Thin/thick films and devices (ferroelectric memory devices, capacitors). Piezoelectric materials and applications (lead-based piezo-ceramics and crystals, lead-free piezoelectrics). Pyroelectric materials and devices Multiferroics (single phase multiferroics, composite ferromagnetic ferroelectric materials). Electrooptic and photonic materials. Energy harvesting and storage materials (polymer, composite, super-capacitor). Phase transitions and structural characterizations. Microwave and milimeterwave dielectrics. Nanostructure, size effects and characterizations. Engineering dielectrics for high voltage applications (insulation, electrical breakdown). Modeling (microstructure evolution and microstructure-property relationships, multiscale modeling of dielectrics).