The phase evolution, electrical stability and chemical compatibility of sealing glass-ceramics for solid oxide fuel cell applications: effect of La sub(2)O sub(3) or CeO sub(2)

In spite of the fact that rare earth oxides can improve the sealing properties of glass-ceramics, the electrical stability of these glass-ceramics under Solid Oxide Fuel Cell (SOFC) operational conditions still remains ambiguous. In this work, the electrical stability of glass-ceramics doped with La sub(2)O sub(3) or CeO sub(2) under SOFC operational conditions has been systematically investigated. The glass-ceramic material with La sub(2)O sub(3) dopant exhibits good electrical stability under SOFC operational conditions; whereas, a decrease in the conductivity of the CeO sub(2)-containing glass-ceramic material can be related to the formation of a conductive phase, i.e., CeO sub(2). In particular, the relationship between the phase evolution and the change in conductivity of glass-ceramics has been clearly demonstrated. Moreover, the sealing glass-ceramics show good chemical compatibility with 8 mol% yttria-stabilized zirconia (8YSZ) electrolyte, after being held at 750 degree C for 1000 hours. The reported results support the suitability of La sub(2)O sub(3)-containing glass-ceramic as a sealing material for SOFC applications.