Síntese e caracterização de filmes finos de Bi1–xLaxFeO3 para aplicações biomédicas

Abstract

In recent years, researches on multifunctional materials has increased considerably. These materials, with emphasis on multiferroics, exhibit simultaneously two (or more) ferroic properties. Multiferroic materials have been used in several applications, such as memories, spintronics, biological (osseointegration) applications, etc. Bismuth ferrite (BiFeO3 or BFO) shows high Curie temperature (ferroelectric transition around 823°C) and high Néel temperature (ferromagnetic transition approximately about 377°C), showing ferroelectric and antiferromagnetic properties simultaneously, at room temperature. However, in previous studies, the methods employed for synthesis resulted in materials with many secondary phases. In this work, the objective of this work is the synthesis and study of pure and modified with lanthanum BFO thin films. The films were synthesized by the Pechini’s method (or polymeric precursor method), and their structural, microstructural and optical characterizations were investigated by X-ray diffraction (XRD), Raman spectroscopy, atomic force microscopy (AFM) and optical absorption techniques (using the integrating sphere technique).