Synthesis, processing and characterization of dielectric compounds exhibiting colossal permittivity

• Grant number: 15/07316-9
• Support Opportunities: Scholarships abroad - Research
• Start date: January 04, 2016
• End date: January 03, 2017
• Field of knowledge: Engineering - Materials and Metallurgical Engineering
• Principal Investigator: Everaldo Nassar Moreira
• Grantee: Everaldo Nassar Moreira
• Host Investigator: Juan Claudio Nino
• Host Institution: Instituto Federal de Educação, Ciência e Tecnologia de São Paulo (IFSP). Campus São João da Boa Vista. São João da Boa Vista , SP, Brazil
• Institution abroad: University of Florida, Gainesville (UF), United States

Abstract

The colossal permittivity property has been attributed to materials that present, independent of frequency over a wide range of temperatures, a dielectric permittivity on several orders of magnitude greater than the solid dielectrics and low dissipation factor too. The development of these materials is much practical interest for use in microelectronics as super capacitors, or devices to store large amounts of energy. Several models have been proposed as a strategy to obtain these materials as well as trying to describe the phenomenon. Mechanisms of surface charges, grain boundary defects, localized dipoles, among others. However, there has been no consensus in the literature between the experimental results, models and ways of preparing these materials. This post-doctoral project aims to investigate the preparation methods and models proposed to explain the origin of colossal dielectric permittivity, noting if these apply to different ferroelectric compounds. The project will be developed in the Department of Materials Science and Engineering, University of Florida (Gainesville, USA), under the supervision of Professor Juan Claudio Nino, which develops interdisciplinary research in the field of ceramic materials (AU)