Zirconia aging effect

Scandia doped zirconia (SDZ) is quite attractive as the electrolyte for SOFC s, especially for the intermediate temperature (600-800 °C) SOFC s. The long-term stability was not clarified before Yamamoto et al. reported the aging effect by annealing at higher temperatures [27]. Zr02 with 8 mol %... 

Fio. 35. (a) The concept of complex oxide of zirconia, titania and alumina (AZT) and (b) its effect on thermal durability after thermal aging test at 1,000°C. 

Hattori, M. et al.. Effect of aging on conductivity of yttria stabilized zirconia, J. Power Sources 126 (2004) 23-27. 

Early data with zirconia-stabilized ceria showed a major improvement over ceria by itself After aging at 1050 C, FTP testing showed sharp decreases in tailpipe concentrations of CO and NOx, together with smaller ceria particle sizes. This argued for effective structural stabilization. 

Kondoh J, Kawashima T, Kikuchi S, Tomii Y, Ito Y (1998a) Effect of aging on yttria-stabUized zirconia. J Electrochem Soc 145 1527-1536... 

Service time. While the volume conductivity of a soUd-state electrolyte such as fully stabihzed (cubic) zirconia (FSZ) reaches a steady state within a comparatively short time, its grain boundary conductivity changes with service time, mostly due to the accumulation of impurities. In PSZ, similar effects occur in relation to the precipitation of tetragonal Zr02 and associated deterioration of conductivity. Because of this aging behavior of PSZ, FSZ is preferred in SOFC applications (Subbarao, 1981 Minh and Takahashi, 1995). 

Kondoh, J., Kawashima, T., Kikuchi, S., Tomii, Y, and lto,Y. Effect of aging on yttria-stabilized zirconia 111. A study of the effect of local structures on conductivity, y. Electrochem. Soc. 1998,145, 1550-1560. 

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