Structure and high temperature physical properties of glass seal materials in solid oxide electrolysis cell

• Published in: Journal of power sources 2012-09, Vol.214, p.75-83
• Main Authors: Hao, Jie, Zan, Qingfeng, Ai, Desheng, Ma, Jingtao, Deng, Changsheng, Xu, Jingming
• Format: Article
• Language: English
• Subjects: Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; Glass-ceramic; Infrared spectra; Solid oxide electrolyzes/fuel cells; Stability; Thermal expansion coefficient; Wetting ability
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2012.03.087

Three series of BaO–CaO–SiO2–Al2O3, SrO–SiO2–Al2O3, and SrO–CaO–SiO2–Al2O3 glasses are prepared. Their basic physical properties are measured using dilatometry and differential scanning calorimetry from room temperature to the softening temperature. Their structures are characterized with infrared spectroscopy. The wetting characteristics of all glasses are examined by monitoring the change in shape of a cube specimen on crofer22 substrates from room temperature to flow temperature with a high temperature shape microscope. Five main absorption bands can be distinguished in the infrared absorption spectra of the three systems. The optimum ranges of sealing temperature of the glasses are determined. The 24SrO–16CaO–25SiO2–8Al2O3 glass is found to be the best sealant for the solid oxide electrolyzer/fuel cells under low loading without leakage. SrO improves the wetting ability of the glass by decreasing the contact angle between the glass and crofer22 substrates. The thermal properties of all the glasses fulfill the requirements for sealing solid oxide electrolysis/fuel cells. In terms of air tightness, the SrO-containing glass shows the best wetting ability among other glasses, and is the most suitable sealant for planar solid oxide electrolyzers/fuel cells. ► Three series of glasses were prepared, and their physical properties were compared. ► The structures were characterized with infrared spectroscopy. ► The wetting characteristics of all glasses were examined. ► The SrO containing glass showed the best wetting ability among other glasses.