Banca de QUALIFICAÇÃO: JOÃO DE MEDEIROS DANTAS NETO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : JOÃO DE MEDEIROS DANTAS NETO
DATE: 30/01/2025
TIME: 09:00
LOCAL: Online via Google Meet
TITLE:

 INFLUENCE OF SURFACE TREATMENTS ON TNO/NiFe HETEROSTRUCTURES

KEY WORDS:

Lithium-ion batteries, heterostructure, TiNb2O7

PAGES: 79
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUMMARY:

With the growing global demand for energy and the need to reduce the use of fossil
fuels, the development of efficient renewable energy storage systems has become a priority. In
this context, lithium-ion batteries (LIBs) stand out as a promising alternative. This has led to
the initiative to investigate a TiNb₂O₇/Ni₈₁Fe₁₉ heterostructure, obtained through the
combination of tape casting and magnetron sputtering techniques, with the goal of exploring its
potential applications in this type of battery. The materials were characterized with a focus on
structural, morphological, electrical, dielectric, and magnetic properties. To improve the surface
quality of the substrates and enable better integration with NiFe thin films, surface treatments
were performed. The results showed an approximately 80% reduction in surface roughness,
leading to a significant 90% decrease in electrical resistance, which dropped from 4.38 kΩ to
0.27 kΩ after polishing. Magnetic properties were also affected, with a notable reduction in
saturation and coercive fields, as the coercive field decreased from 13 Oe to 4 Oe with
intensified polishing. These results demonstrate the success of the polishing process in
enhancing the electrical and magnetic properties of the heterostructure. The combination of tape
casting and polishing proved to be an effective approach for producing TNO substrates with
potential applications in batteries. The integration of LIB components with ferromagnetic layers
aligns with recent research on the use of magnetic fields in ionic dynamics, driving the
development of advanced battery technologies

COMMITTEE MEMBERS:
Presidente - 1474380 - MARCIO ASSOLIN CORREA
Interno - 1149564 - WILSON ACCHAR
Externo ao Programa - 3365252 - JOAO CARLOS ROCHA DE ARAUJO - UFRNExterno à Instituição - DANNIEL FERREIRA DE OLIVEIRA