Evaluation of Properties Changes by the Addition of Surfactant in the Synthesis of Ni/CeO2

Autor(es)

Ricci, Lucas S. ; Lucas, Marcela A. ; de Souza, Joao C. P. ; Possato, Luiz G.

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 27, p. 8-pg., 2024-01-01.

Resumo

This work evaluates how adding cetyltrimethylammonium bromide (CTAB) in the synthesis affects the physical and chemical features of Ni/CeO2 catalysts. The samples were characterized by the Rietveld refinement from X-ray diffraction (XRD) and showed a decrease in the crystallite size and an increase in the microstrain from 5.9 to 7.5 x 10-3. Nitrogen physisorption analysis was used to obtain the pore size distribution by the BJH method, varying the pore size between 8 and 12 nm. Raman spectroscopy was employed to confirm the fluorite structure arrangement of ceria and the number of vacancies in the bulk phase, where the ratio from vibrational modes related to defects and oxygen vacancies increased from 0.488 to 0.516 ratio. With the spectra obtained from X-ray photoelectron spectroscopy (XPS), it was possible to observe the distribution of metals on the surface of the samples and their oxidative states, providing clues about the quantity of vacancies. Samples with higher concentrations of CTAB obtained higher values of Ce3+, reaching a 0.45 ratio on the surface. The scanning electron microscopy (SEM) analysis showed that the addition of CTAB formed more irregular shape grains, reaching 20 mu m of medium size for all the samples. (AU)

• Processo FAPESP: 23/03754-8 - Avaliação de surfactantes e promotores na síntese de catalisadores Ni/CeO2: um estudo operando
• Beneficiário: Lucas da Silva Ricci
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 23/04143-2 - Avaliação quimiométrica de catalisadores Ni/CeO2 na reação de redução de CO2 obtidos por coprecipitação: um estudo operando
• Beneficiário: Matheus Silva de Assis
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 21/05246-4 - Estudos in situ e operando de catalisadores heterogêneos para a conversão de CO2
• Beneficiário: Luiz Gustavo Possato
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 22/14265-5 - Estudos in situ e operando de catalisadores heterogêneos para a conversão de CO2
• Beneficiário: Luiz Gustavo Possato
• Modalidade de apoio: Bolsas no Brasil - Jovens Pesquisadores