Synthesis and characterization of nanoestrutured multiferroics bulk ceramics produced via Spark Plasma Sintering - SPS

• Grant number: 19/12237-1
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: August 01, 2019
• End date: March 09, 2021
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: José Antonio Eiras
• Grantee: Giovani Martim Albuquerque
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 17/13769-1 - Multiferroic and ferroelectric materials for energy converters: synthesis, properties, phenomenology and applications, AP.TEM

Abstract

Multiferroic materials are those that have ordered subsystems (magnetic, ferroelectric and ferroelastic). The effects resulting from the interaction between these subsystems are of great interest in both fundamental research and technological development. On the other hand, the need for miniaturization of electronic devices has aroused interest in the investigation of the effect of size and dimensionality on the properties of these subsystems and their interactions in nanometric scale materials. Based on this premise, it is proposed in this project to obtain nanostructured bulk ceramics of multiferroic materials to investigate their properties with dimensional scale evolution (from micro to nanometric). The materials to be analyzed are iron and lead niobate, Pb (Fe1/2Nb1/2) O3 (PFN) and iron and lead titanate, Pb (FexTi1-x) O3 (PFTi) modified with SnO2, both multiferroic materials. The powders will be obtained by the method of columbite, followed by milling by the micro-grinding technique in order to obtain particles with particle size distribution suitable for the processing of ceramic bodies with the desired microstructure. On the other hand, the microstructural control (combining high densification rates with the desired grain size) of the ceramic bodies will be carried out by the "Spark Plasma Sintering" (SPS) technique. Alternative techniques for the synthesis of nanostructured powders (such as combustion or chemical routes) and for the processing of ceramic bodies (such as microwave sintering, hot pressing and fast sintering) will be carried out in collaboration with other team. Electrical, dielectric, ferroelectric, magnetoelectric, piezoelectric and photovoltaic characterizations will be analyzed for factors such as grain size (and/or dimensionality) dependence, to compare the results with current models or to propose new phenomenological models that describe the observed response. It should be noted that the SPS technique has already been implemented in the Ferrous Materials Group and presented promising results in the production of nanostructured materials. This project also intends to support the training of human resources in the area of nanostructured materials and nanotechnology. The project will be carried out in collaboration with other research groups, both belonging to the thematic project team to which it is linked, as well as to other national and international groups. (AU)