EFFECT OF ATTRITION MILLING AND CALCINATION TEMPERATURE ON PHASE COMPOSITION OF STRONTIUM- AND MAGNESIUM-DOPED LANTHANUM GALLATE

Oxygen-ion conductors based on strontium- and magnesium-doped lanthanum gallate have been proposed to be used as solid electrolyte in solid oxide fuel cells operating at intermediate temperatures (500-700 degrees C), due to their high ionic conductivity and stability over a wide range of oxygen partial pressures. In this work, the effect of attrition milling on phase composition of powder and consolidated specimens prepared by solid state synthesis has been investigated. The results show that both the attrition milling and the calcination temperature play a major role in the phase composition. Powders with negligible amount of secondary phases were obtained after two steps of calcination at high temperature followed by attrition milling.