Electric field-assisted sintering (gadolinia-doped ceria/alkali salts) composite membranes

Autor(es)

Carvalho, S. G. M. ^[1] ; Muccillo, E. N. S. ^{[1, 2]} ; Marques, F. M. B. ^[3] ; Muccillo, R. ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Energy & Nucl Res Inst IPEN, Ctr Sci & Technol Mat CCTM, BR-05508000 Sao Paulo, SP - Brazil

^[2] Marques, F. M. B., Univ Aveiro, Dept Mat Engn \& Ceram, Aveiro, Portugal.Carvalho, S. G. M., Energy & Nucl Res Inst IPEN, Ctr Sci & Technol Mat CCTM, BR-05508000 Sao Paulo, SP - Brazil

^[3] Univ Aveiro, Dept Mat Engn & Ceram, Aveiro - Portugal

• Tipo de documento: Artigo Científico
• Fonte: MATERIALIA; v. 11, JUN 2020.
• Citações Web of Science: 0

Resumo

Composite ceramic membranes were prepared according to two routes: (i) vacuum impregnation of molten eutectic sodium-lithium carbonates (NLC) into porous ceria-20 mol% gadolinia (20GDC) solid electrolytes; (ii) electric field-assisted sintering of a 25 wt% NLC/75 wt% 20GDC mixture. Porous 20GDC ceramics were obtained by controlled thermal removal of 40 vol%KCl added as pore former. Electric field-assisted (flash) sintering was carried out monitoring thickness during application of 200 V cm(-1) to the specimen positioned in a sample chamber inserted in a vertical dilatometer. The surfaces of the sintered membranes were observed in a scanning electron microscope. Electrochemical impedance spectroscopy measurements were performed in the 5 Hz to 13 MHz frequency range in the 280-580 degrees C range. Arrhenius plots showed the transition from oxide ion conduction (due to the solid electrolyte) to carbonate ion conduction (due to the molten NLC). Membranes flash sintered at 420 degrees C in 2 min showed electrical conductivity similar to membranes conventionally sintered at 690 degrees C for 2 h. (AU)

• Processo FAPESP: 17/11937-4 - Rota sustentável para a conversão de metano com tecnologias eletroquímicas avançadas
• Beneficiário: Fabio Coral Fonseca
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia
• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs