Eletrocerâmica multiferróica: produção e caracterização por difração de raios-x da matriz BiFeO3

Abstract

This paper aims to present and discuss the results of measurements of X-ray diffraction performed to characterize electroceramics composite material BiFeO3 (BFO) with additives bismuth oxide (Bi2O3) and lead oxide (PbO). BFO matrix was produced by the solid-state reaction standard method. The additives were used at a concentration of 10% by weight. The binders used to improve the densification of the samples were polyvinyl alcohol (PVA) and tetraethyl orthosilicate (TEOS). The diffraction peaks for all patterns can be identified for the major phase with a rhombohedral structure of space group R3c, as indicated by the Rietveld refinement was performed. There was formation of secondary phases Bi2Fe4O9 and Bi25FeO40. The density of ceramics was determined theoretically and experimentally by the method of Archimedes. BiFeO3 is a perovskite-type ABO3 and is also known as magnetoelectric multiferroic, whose ferromagnetic or antiferromagnetic properties can be controlled from the application of an external electric field, or ferroelectric properties can be controlled from the application of an external magnetic field. All samples were investigated in view of possible applications in electronic circuits, in the form of components for use in electronic devices.