Cation-doping effects on the conductivities of the mayenite Ca12Al14O33

Abstract

The mayenite Ca12Al14O33 material, owing to its oxide ion conducting behavior and the low cost of raw materials, has the potential of being applied in solid oxide fuel cells as an electrolyte. However, suffering from the relatively low oxide ion conductivity, there is still a long way to go for its practical application. To enhance the oxide ion conduction in Ca12Al14O33, many efforts have been endowed to this from different research groups but hardly succeeded. In this work, the Ca12Al14O33-based materials with Y, In, and Cu-doping on the Ca or Al sites were fabricated through a traditional solid-state reaction method (for Y-doping on Ca and Cu-doping on Al) or a glass-crystallization method (for In-doping on Al), with their electrical conductivities being studied. The results revealed that the solid solution regions of Ca12−x YxAl14O33+δ , Ca12Al14−x InxO33, and Ca12Al14−x CuxO33−δ were 0 ≤ x ≤ 0.15, 0 ≤ x ≤ 0.1, and 0 ≤ x ≤ 0.3, respectively. The electrical conductivities of all these doped materials were investigated.

Keywords

• high temperature solid oxide fuel cells
• oxide ion conductors
• mayenite ca12al14o33
• cation-doping
• conductivity