Scandia stabilized zirconia

Solid Oxide Fuel Cells Materials Properties and Performance 

FIGURE 1.5 Conductivity isotherms in the zirconia-scandia system at 750, 850, and 950°C [30], 

FIGURE 1.6 Conductivity of zirconia-scandia system with a different scandia ratio. 

Another issue with ScSZ is that there is a decrease in conductivity at around 580°C as indicated by broken lines in two of the curves for higher scandia contents, 10.0 to 12.0 mol%. With high scandia contents, the cubic phase transforms to a lower conductivity rhombohedral phase, the p phase, at lower temperatures [25], The phase change can be avoided by limiting the scandia content to 8 mole% [25] or by codoping with other oxides, such as those of bismuth [36] or ytterbium [37], 

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FIGURE 1.3 Conductivity of yttria- and scandia-stabilized zirconia in air at 1000°C. (Data from Fergus, J.W., J. Power Sources, 162, 30, 2006.)... 

Sholklapper et al. [204] studied the structure and performance stability of a nanoparticle-infiltrated LSM in porous scandia-stabilized zirconia (SSZ) electrode at 650°C. The infiltrated LSM particles were 100 nm in diameter and some orientation alignment of the LSM nanoparticles within SSZ was observed after the cathodic polarization at 150 mAcnr2 for 500 h. However, there is no voltage degradation under the conditions studied. 

Scandia-stabilized zirconia electrolyte with standard SOFC electrodes is used to construct the cells. Stacks are constructed using stainless steel interconnects. The surfaces of the stainless steel are treated to provide an electrically conductive scale with low-scale growth rate. The performance characteristics of a single cell (2.5 cm active area) and a 25-cell stack (active area of 64 cm per cell) are shown in hgure 3.5 and hgure 3.6. The performance stability of the stack is shown in hgure 3.7. 

W.W. Barker, F.P. Bailey, and W. Garrett, A high-temperature neutron diffraction study of pure and scandia-stabilized zirconia, J. Solid State Chem. 7, 448—453 (1973). 

AN OVERVIEW OF SCANDIA STABILIZED ZIRCONIA ELECTROLYTE DEVELOPMENT FOR SOFC APPLICATION... 

Scandia Stabilized Zirconia (ScSZ) shows good potential for SOFC application because of its high electrical conductivity. But, the fundamental study such as suitable composition, mechanical properties and chemical stability are insufficient to compare with Yttria Stabilized Zirconia (YSZ) which is promising material for SOFC application. 

Overview of Scandia Stabilized Zirconia Electrolyte Development for SOFC Application... 

Scandia-stabilized zirconia (ScSZ) possesses the highest oxygen-ion conductivity among all zirconia-based oxides, and therefore represents a promising solid electrolyte for applications in electrochemical devices such as solid oxide fuel cells (SO PCs) and catalytic membrane reactors (further details are available in Section 1.6.6.3). 

Diffusion of the stable Zr tracer isotope in 12mol% poly crystalline scandia-stabilized zirconia was studied in air at 1200 to 1600C. Secondary ion mass spectroscopy was used to record the tracer diffusion profiles. The diffusivities for bulk and grain boundary diffusion were given by,... 

Laguna-Bercero MA, Kilner JA, Skinner SJ (2011) Development of oxygen electrodes for reversible solid oxide fuel cells with scandia stabilized zirconia electrolytes. Solid State Ionics 192 501-504. doi 10.1016/j.ssi.2010.01.003... 

Fig. 19.10 Changes in internal stress of a Scandia stabilized zirconia electrolyte and NiO-YSZ anode as determined by in situ synchrotron measurements. (Reproduced with permissions Sumi et al. J Fuel cell Sci Tech)...

Vijaya Lakshmi, V. and Bauri, R. (2011) Phase formation and ionic conductivity studies on ytterbia co.floped scandia stabilized zirconia (O.9 O2 O.O9SC2O3-0.01Yb203) electrolyte for... 

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