Particle size and doping effect on structural and magnetic properties of yttrium iron garnets obtained in the hydrothermal microwave method

• Grant number: 19/10918-1
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: July 01, 2019
• End date: September 30, 2019
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Alexandre Zirpoli Simões
• Grantee: Barbara Sartorelli Caldeira
• Supervisor: Ulf Wiedwald
• Host Institution: Faculdade de Engenharia (FEG). Universidade Estadual Paulista (UNESP). Campus de Guaratinguetá. Guaratinguetá , SP, Brazil
• Institution abroad: University of Duisburg-Essen, Germany
• Associated to the scholarship: 18/07212-7 - Magnetohyperthermia applied to nanoparticles with garnet structure: funcionalization and encapsulation studies in thermosetting polymers, BP.IC

Abstract

Ferrite materials have been investigated over the years because they are versatile materials. The garnet structure is one of the most abundant iron oxide phases, it has many applicable properties such as: magnetic, magneto-optical, electrical, radiation stability and others. Therefore, it can be used in microwave circulators, optical isolators, or phase shifters. Its importance can be attributed to the flexibility as many parameters can be tuned to obtain properties at will. For example, the magnetic properties can be varied by size and doping effects. Considering microwave assisted hydrothermal synthesis, the particle size can be shifted by the choice of the synthesis parameters, such as temperature and time. As reported for the yttrium iron garnet (YIG), doping with aluminum can tune the magnetic response for microwave and biomedical applications. In the proposed work, YIG and Aluminum-doped YIG nanoparticles with various nanoparticle diameters and Al doping levels obtained by the microwave assisted hydrothermal method and calcinated at various temperatures and time were investigated by means of structural, morphological and magnetic properties. Numerous techniques such as x-ray diffraction (XRD), scanning electron microscope (SEM), high-resolution transmission electron microscope (HRTEM), energy dispersive x-ray spectroscopy (EDX), magnetometry and ferromagnetic resonance (FMR) will now be used to collect the necessary information for a thorough understanding of Al-doping in YIG. It is expected that both groups, in Brazil and Germany, will deepen the knowledge in the factors which influence in magnetic properties in YIG and Al-doped YIG. Additionally, the proposer will have an abroad experience and learn advanced characterization techniques like HRTEM or FMR with a team of worldwide experts in the field of magnetic nanostructures. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

OLIVEIRA, L. L.; CORTES, J. A.; CALDEIRA, B. S.; STRUSCH, T.; WIEDWALD, U.; SIMOES, A. Z.. Structural, electronic paramagnetic resonance and magnetic properties of praseodymium-doped rare earth CeO2 semiconductors. CERAMICS INTERNATIONAL, v. 47, n. 15, p. 20768-20780, AUG 1 2021. (13/07296-2, 19/10918-1)