Solid oxide cells (SOCs) offer great potential for clean and efficient power generation from a wide variety of fuels, ranging from hydrocarbons to renewables, and for highly efficient conversion of electricity to hydrogen or synthesis gas via electrolysis. Performances of these devices are determined by the durability of different types of functional materials. The development of appropriate sealant materials represents one of the major challenges for the assembly of a durable SOC stack. The main role of the sealant is to prevent the mixing and leaking of fuel within the stack, to electrically isolate cells and to provide mechanical bonding with adjoining components.