Banca de QUALIFICAÇÃO: NÍVIA LUCIANA COSTA DE SIQUEIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : NÍVIA LUCIANA COSTA DE SIQUEIRA
DATE: 13/04/2026
TIME: 16:30
LOCAL: Online - via GOOGLE Meeting
TITLE:

Optimization of the thermoelectric response in ZrO₂–BaTiO₃ heterostructures with NiFe ferromagnetic thin films deposited by magnetron sputtering.

KEY WORDS:

zirconia; barium titanate; NiFe; anomalous Nernst effect.

PAGES: 75
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUMMARY:

The increasing demand for alternative energy sources has driven the development of technologies capable of harvesting waste heat through thermomagnetic phenomena. In this context, ceramic/metal heterostructures stand out as promising systems due to their ability to integrate thermal, structural, and magnetic properties into multifunctional platforms. This study aims to investigate how the composition of the ceramic substrate and its structural and microstructural features influence voltage generation and the thermoelectric performance based on the Anomalous Nernst Effect (ANE). Ceramic tapes with different BaTiO₃ contents (ZB0, ZB20, and ZB60) were produced using the tape casting technique, followed by the deposition of Ni81Fe19 thin films via magnetron sputtering. The samples were characterized by X-ray diffraction, scanning electron microscopy with energy-dispersive spectroscopy, and magnetic measurements using a vibrating sample magnetometer. Partial results indicate the formation of a multiphase system and suggest that increasing BaTiO₃ content promotes microstructural changes in the ceramic tapes, such as higher porosity and surface irregularity. The heterostructures exhibit soft ferromagnetic behavior, with variations in magnetic parameters that may be associated with substrate characteristics. Ongoing work includes surface roughness analysis by atomic force microscopy and the evaluation of thermoelectric properties, aiming to establish comprehensive correlations between structure, microstructure, and thermoelectric response.

COMMITTEE MEMBERS:
Presidente - 1474380 - MARCIO ASSOLIN CORREA
Interno - 3485163 - NIVALDO FREIRE DE ANDRADE NETO
Interna - 1481705 - SALETE MARTINS ALVES
Externo à Instituição - RICARDO BARRETO DA SILVA