Banca de DEFESA: DIEGO ANÍSIO MODESTO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : DIEGO ANÍSIO MODESTO
DATA : 23/02/2022
HORA: 14:00
LOCAL: por participação remota
TÍTULO:

Analysis of the influence of sol-gel viscosity on the physical properties of superconducting and ferromagnetic nanostructures obtained by electrospinning and membrane filling

PÁGINAS: 100
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Cerâmicos
RESUMO:

With the advances in nanoscience, the development of nanostructures-based equipment has a great impact on the production of scientific knowledge, as well as on the process of technological innovation and, consequently, on contributions to society. The development of devices for spintronics, single-photon detectors, magnetoresistance systems and nanoSQUIDs are some interesting examples of nanostructures applications with superconducting materials, such as YBa₂Cu₃O_7-δ, and ferromagnetics such as La_1-xSr_xMnO₃. To enable the production of these technologies, it is necessary to understand all stages of the process, mainly the synthesis, and how some parameters can influence the properties of the final material. Thus, the present work aims to analyze how viscosity in the sol-gel methodology can influence the synthesis by different techniques and the physical properties of materials after heat treatment. For this purpose, electrospinning and nanoporous membrane filling techniques were used to obtain the nanostructures. A new methodology of chemical route by sol-gel was developed using organometallic precursors, organic acids and alcohol without polymer addition. Thus, using different sol-gel viscosities, electronspun YBCO nanofibers and LSMO nanotubes filled with YBCO were obtained. By means of X-ray diffractometry, the crystalline phases of each synthesized compound were identified. The morphology of the nanostructures was analyzed by scanning electron microscopy, proving the formation of nanofibers and filled nanotubes. Magnetic measurements of each compound were performed using a SQUID magnetometer. The obtained results indicate that there is viability of sol-gel formation by electrospinning technique without polymer addition according to fluid viscosity control. The synthesized samples presented the expected crystalline phases, confirmed by magnetization measurements.

MEMBROS DA BANCA:
Presidente - Interno ao Programa - 2604128 - ALEXANDRE JOSE DE CASTRO LANFREDI
Membro Titular - Examinador(a) Interno ao Programa - 1669182 - JOSE FERNANDO QUEIRUGA REY
Membro Titular - Examinador(a) Interno ao Programa - 1761120 - DANILO JUSTINO CARASTAN
Membro Titular - Examinador(a) Externo à Instituição - ELAINE CRISTINA PARIS - EMBRAPA
Membro Titular - Examinador(a) Externo à Instituição - ANA PAULA DE AZEVEDO MARQUES - UNIFESP
Membro Suplente - Examinador(a) Interno ao Programa - 1671292 - SYDNEY FERREIRA SANTOS
Membro Suplente - Examinador(a) Externo ao Programa - 2604737 - EVERALDO CARLOS VENANCIO
Membro Suplente - Examinador(a) Externo à Instituição - FÁBIO CORAL FONSECA - IPEN