Stable sealing glass for planar solid oxide fuel cell

The thermal and chemical stability of glasses in the BaO–Al2O3–La2O3–B2O3–SiO2 system were investigated as well as bonding characteristics and wetting behavior to yttria stabilized zirconia (YSZ) electrolyte, to develop a suitable sealing glass for planar solid oxide fuel cell operating at 800–850 °C. The thermal properties such as glass transition temperature, softening temperature and thermal expansion coefficient were found to depend on the B2O3:SiO2 ratio in glass composition; thus the bonding characteristics of the glass to YSZ were also influenced by this ratio. The glass having a minimum thermal expansion mismatch with YSZ showed an excellent endurance during thermal cycling. No interface reaction was observed for all the glass/YSZ specimens heat-treated at 800–850 °C up to 100 h.