Influence of the synthesis method on the porosity, microstructure and electrical properties of La0.7Sr0.3MnO3 cathode materials

• Published in: Materials characterization 2009, Vol.60 (12), p.1417-1423
• Main Authors: DA CONCEICAO, Leandro, SILVA, Camila R. B, RIBEIRO, Nielson F. P, SOUZA, Mariana M. V. M
• Format: Article
• Language: English
• Subjects: Cathodes; Citrates; Combustion; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Microstructure; Nanomaterials; Nanostructure; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Porosity; Solidification; Synthesis
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2009.06.017

Lanthanum strontium manganite (La1-xSrxMnO3, LSM) is a promising material for cathodes in solid oxide fuel cells. La0.7Sr0.3MnO3 nanopowders were synthesised by three different methods (combustion, citrate and solid-state) and characterised by thermal analysis, XRD, N2 adsorption and SEM. All powders exhibited single LSM phase formation with crystallite sizes in the range 12-20 nm. Nanopowders were sintered at 1100 C to produce porous pellets. The porosity, particle size and microstructure of LSM sintered bodies depend strongly on the preparation methodology. The samples synthesised by the combustion and citrate methods had smaller particle sizes and higher porosity after sintering than those derived from solid-state synthesis. However, the electrical conductivity, measured by two-probe technique, was similar for all three samples.