Effect of the sintering conditions on the morphology of La9.33Si2Ge4O26 oxyapatite for SOFCs electrolytes

• Autor(a) principal: Macatrão, Mafalda
• Data de Publicação: 2013
• Outros Autores: Santos, Mário João dos, Alves, Cátia, Oliveira, Fernando Almeida Costa, Marcelo, Teresa, Mascarenhas, João, Trindade, B.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.9/2187
• topic: SOFC; Electrolytes; Sintering

Solid oxide fuel cells (SOFCs) are devices that allow direct conversion of chemical to electrical energy through an electrochemical reaction in a cleaner and more efficient way than conventional processes (eg. gas turbines). They are characterized by the use of a solid oxide material as the electrolyte. Yttria-stabilised zirconia (YSZ) has traditionally been used in SOFCs electrolytes at temperatures in the range of 850-1000 °C. Recent research is being focused on the development of new materials with increased ionic conductivity at intermediate temperatures (500-800ºC) as alternative materials to YSZ. Rare earth silicates with an apatite-type structure, such as doped lanthanum oxides of general formula La10(MO4)6O2, where M = Ge, Co, Si, Al, or P, are among these materials. The major limitation associated with the manufacture of these materials is their poor sinterability, which requires high sintering temperatures (1600ºC).