Solid Electrolyte Materials, Devices, and Applications

• Published in: Journal of electroceramics 2004-07, Vol.13 (1-3), p.619-625
• Main Authors: Joshi, Ashok V, Steppan, James J, Taylor, Dale M, Elangovan, S
• Format: Article
• Language: English
• Subjects: Devices; Direct power generation; Driving; Electronics; Fuel cells; Gas pipelines; Solid electrolytes; Solid oxide fuel cells; Synthesis gas
• ISSN: 1385-3449; 1573-8663
• DOI: 10.1007/s10832-004-5168-x

The development of ionically conducting doped ceria and its application as a solid electrolyte is described. Ceria exhibits enhanced ionic conductivity at elevated temperatures when doped with rare earth oxides, particularly Gd and Sm. Sintering aids, particularly titania, are used to achieve zero open porosity at acceptable sintering temperatures. Doped ceria membranes, which exhibited oxygen permeability at elevated temperatures, have been used to construct electrochemical devices for the production of high purity oxygen. Sr and Mg doped lanthanum gallate compositions are under development for use in solid oxide fuel cells operating at intermediate temperatures. These materials have the same ionic conductivity at 800 C as that of YSZ at 1000 C, but development work is still required to prevent degradation at the anode-electrolyte interface. Also under development are mixed ionic and electronic conducting membranes which are permeable to oxygen under pressure, to generate high purity oxygen; or under the driving force of a chemical reaction to produce synthesis gas from methane. 41 refs.