Growth and characterization of lead-free piezoelectric single crystals

• Grant number: 24/03661-2
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: September 01, 2024
• End date: June 30, 2025
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: José Antonio Eiras
• Grantee: Thissiana da Cunha Fernandes
• Host Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Federal de São Paulo (UNIFESP). Campus São José dos Campos. São José dos Campos , SP, Brazil
• Associated research grant: 17/13769-1 - Multiferroic and ferroelectric materials for energy converters: synthesis, properties, phenomenology and applications, AP.TEM
• Associated scholarship(s): 24/13436-6 - Characterization and manipulation of domain structures in lead-free ferroelectric single crystals produced by vertical Bridgman route, BE.EP.DD

Abstract

This project proposes the investigation of dielectric, ferroelectric, piezoelectric and photovoltaic, in addition to phenomenological analyses, in single crystals of (K,Na)NbO3 doped with CuO (KNN-Cu), (K,Na,Li)(Nb,Ta,Sb)O3 (KNN-LTS) and (K,Ba)(Nb,Ni)O3 (KBNN) grown by the vertical Bridgman-Stockbarger method. The growth of the KNN-Cu composition will be carried out based on the experience gained through of the successes achieved in growth for KNN-LTS and KBNN, as well as its complete electrical characterization. Regarding the characterizations of the single crystals already produced until moment, aiming to understand the dielectric behavior of KNN-LTS single crystals, it is proposed to carry out the analysis of domain structures and domain wallsferroelectrics, as well as investigating the relationship between the optical and photovoltaic properties of KBNN single crystals. Optimization of growth parameters will also be carried outto obtain single crystals with large dimensions and high chemical uniformity and structural. To carry out these activities, we request the granting of 7 (seven) months of direct doctoral scholarship for the completion of the doctorate of the scholarship holder, holder of the DD scholarship FAPESP process No. 2019/26807-4.