Sealants for Solid Oxide Fuel Cells

Basic requirements for a sealant are good bonding to the materials of interest, chemical stability in the operating environment, and low gas permeability. For high-temperature operation as in Solid Oxide Fuel Cells (SOFCs), the sealant must also have a thermal expansion which is reasonably close to that of the other materials involved and must have some compliance, or softness, to allow for some mismatch between the components to be joined. In this paper, we discuss a family of glass-ceramic materials with mechanical, chemical, and electrical properties that are suitable for these demanding high-temperature applications