Fabrication of Sr- and Co-doped lanthanum chromite interconnectors for SOFC

Journal Article · Fri Jul 15 04:00:00 EDT 2011 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2011.03.019· OSTI ID:22212196

Setz, L. F.G. ^[1]; Santacruz, I. ^[2]; Mello-Castanho, S. R.H. ^[3]; Moreno, R. ^[4]

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1. Departamento de Engenharia de Materiais, Universidade Federal de Sao Carlos - DEMa/UFSCar (Brazil)
2. Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Universidad de Malaga, 29071 Malaga (Spain)
3. Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN (Brazil)
4. Instituto de Ceramica y Vidrio, ICV (CSIC), 28049 Madrid (Spain)

Graphical abstract: FESEM micrographs of the fresh fracture surfaces for the La{sub 0.80}Sr{sub 0.20}Cr{sub 0.92}Co{sub 0.08}O{sub 3} sintered specimens cast from optimised suspensions with 13.5, 15 and 17.5 vol.% solids loading. Aqueous suspensions were prepared using ammonium polyacrylate (PAA) as dispersant and tetramethylammonium hydroxide (TMAH) to assure a basic pH and providing stabilization. Sintering of the green discs was performed in air at 1600 {sup o}C for 4 h. Highlights: {yields} Optimum casting slips were achieved with 3 wt.% of ammonium polyacrylate and 1 wt.% of tetramethylammonium hydroxide. -- Abstract: Many studies have been performed dealing with the processing conditions of electrodes and electrolytes in solid oxide fuel cells (SOFCs). However, the processing of the interconnector material has received less attention. Lanthanum chromite (LaCrO{sub 3}) is probably the most studied material as SOFCs interconnector. This paper deals with the rheology and casting behaviour of lanthanum chromite based materials to produce interconnectors for SOFCs. A powder with the composition La{sub 0.80}Sr{sub 0.20}Cr{sub 0.92}Co{sub 0.08}O{sub 3} was obtained by combustion synthesis. Aqueous suspensions were prepared to solids loading ranging from 8 to 17.5 vol.%, using ammonium polyacrylate (PAA) as dispersant and tetramethylammonium hydroxide (TMAH) to assure a basic pH and providing stabilization. The influence of the additives concentrations and suspension ball milling time were studied. Suspensions prepared with 24 h ball milling, with 3 wt.% and 1 wt.% of PAA and TMAH, respectively, yielded the best conditions for successful slip casting. Sintering of the green discs was performed in air at 1600 {sup o}C for 4 h leading to relatively dense materials.

• OSTI ID: 22212196
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 7 Vol. 46; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DOPED MATERIALS
ELECTRODES
ELECTROLYTES
MICROSTRUCTURE
MILLING
OXIDES
POWDERS
SINTERING
SLIP CASTING
SOLID OXIDE FUEL CELLS
SOLIDS
STABILIZATION
SURFACES
SUSPENSIONS
SYNTHESIS
X-RAY DIFFRACTION