Banca de QUALIFICAÇÃO: ANTONIO TEOFANES BERTOLLO DE OLIVEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : ANTONIO TEOFANES BERTOLLO DE OLIVEIRA
DATE: 14/03/2023
TIME: 14:00
LOCAL: Santo André
TITLE:

Lanthanum (Strontium) Titanate doped with Copper and Nickel: synthesis, characterization, and nanoparticles production by exsolution for solid oxide fuel cell electyrodes

PAGES: 79
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Cerâmicos
SUMMARY:

Climate emergency has become the century's biggest concern due to the 1.5 ºC increase in the average temperature of the atmosphere, leading soon to a greater impact on natural events. In recent years, several efforts have been made to achieve net-zero emissions, based in the substitution of fossil fuels matrix by decarbonization. Solid Oxide Fuel Cell (SOFC) stands out as a viable alternative due to its high efficiency, fuel flexibility and low-to-zero CO2 emissions. SOFC anodes are responsible for catalyzing the fuel reduction. Among the used materials, ceramic perovskites are electrodes good candidates due to its high mixed ionic electronic conductivity and chemical and thermal stability. The present work seeks to obtain exsolved metal alloys nanoparticles attached on perovskites structure with the aim to address a more promising material, challenging and less contemplated in the literature. The nanoparticles catalysts solubilized into a perovskite host were exposed to a reducing H2 atmosphere. The La0.8Sr0.2Ti0.7Ni0.3-xCuxO3 (x=0.1, 0.15, 0.2) were obtained by the Pechini synthesis route and calcined at 1000 °C for 5 hours. To obtain decorated NiCu nanoparticles, the powders were heat-treated under 3 vol% H2/N2 atmosphere at 900 ºC for 10 hours. The samples characterization was performed by TGA/DTA, dilatometry, scanning electron microscope, X-ray diffraction, XPS, and EIS. Rietveld’s refinement was used to determine structural parameters like crystal symmetry, crystallite size and phase content. With preliminary results, it is possible to conclude that the chosen synthesis route and the reduction treatment was successful in obtain NiCu particles alloy. Electrochemical Impedance Spectroscopy reveled that La0.8Sr0.2Ti0.7Ni0.15Cu0.15O3-δ exhibited the maximum conductivity of 8.06 x 10-3 S cm-1 in air atmosphere at 961 K.

COMMITTEE MEMBERS:
Presidente - Interno ao Programa - 1545738 - MARCIA TSUYAMA ESCOTE
Membro Titular - Examinador(a) Interno ao Programa - 1671394 - HUMBERTO NAOYUKI YOSHIMURA
Membro Titular - Examinador(a) Externo à Instituição - CRISTIANE BARBIERI RODELLA
Membro Suplente - Examinador(a) Interno ao Programa - 1760527 - FLAVIO LEANDRO DE SOUZA
Membro Suplente - Examinador(a) Interno ao Programa - 2605463 - JOSE ANTONIO SOUZA
Membro Suplente - Examinador(a) Externo à Instituição - FÁBIO CORAL FONSECA