Thermal Stability Investigation of a Newly Developed Sealing Glass as IT-SOFC Sealant

A sealing glass, based on the SiO2-B2O3-BaO-La2O3-ZrO2-Y2O3 system, was developed for intermediate temperature solid oxide fuel cells (ITSOFCs). The coefficient of thermal expansion (CTE) of the glass is 9.8×10-6/K (RT~631℃), very close to that of 8YSZ electrolyte. The glass shows a very good thermal stability, even after heat-treatment at 700℃for 300h, little change in CTE detected. The investigations also reveal that the glass is chemically compatible with 8YSZ electrolyte and no obyious interfacial reaction can be observed after the glass contacting with 8YSZ at 700℃for 300h.