Perovskite solid oxide

Double Substitution In such processes, two substitutions take place simultaneously. For example, in perovskite oxides, La may be replaced by Sr at the same time as Co is replaced by Fe to give solid solutions Lai Sr Coi yFey03 5. These materials exhibit mixed ionic and electronic conduction at high temperatures and have been used in a number of applications, including solid oxide fuel cells and oxygen separation. 

The Brouwer diagram approach can be illustrated with reference to the perovskite structure oxide system BaYbvPr VC>3, which has been explored as a potential cathode material for use in solid oxide fuel cells. The parent phase... 

The use of this approach can be illustrated by the perovskite structure proton conductor BaYo.2Zro.gO3 g- This material has been investigated for possible use in solid oxide fuel cells, hydrogen sensors and pumps, and as catalysts. It is similar to the BaPr03 oxide described above. The parent phase is Ba2+Zr4+03, and doping with... 

Mai A, HaanappelVAC, UhlenbruckS, TietzF, and Stover D. Ferrite-based perovskites as cathode materials for anode-supported solid oxide fuel cells, Part I. Variation of composition. Solid State Ionics 2006 176 1341-1350. 

Huang Y-H, Dass RI, Xing Z-L, and Goodenough JB. Double perovskites as anode materials for solid oxide fuel cells. Science 2006 312 254—256. 

Franco T, HoshiarDin Z, Szabo P, Lang M, and Schiller G. Plasma sprayed diffusion barrier layers based on doped perovskite-type LaCr03 at substrate-anode interface in solid oxide fuel cells. J. Fuel Cell Sci. Technol. 2007 4 406-412. 

Solid oxide catalysts such as hexaaluminates and perovskites, in which an active metal catalyst is incorporated into a coke-resistant lattice, are effective for liquid hydrocarbon reforming due to their thermal stability over a broad-range of temperature. However, sulfur tolerance of those materials has yet to be demonstrated. 

For some applications, such as the cathode materials in solid oxide fuel cells (see Section 5.4.4), a material is needed that can conduct both ions and electrons. The strontium-doped perovskites LaMn03 (LSM), and LaCr03 (LSC) have both these properties. 

Helmut Ullmann, Nikolai Trofimenko, Composition, structure and transport properties of perovskite-type oxides , Solid State Ionics 119,1-8 (1999). 

Figure 12. Scheme displaying the Jahn—Teller distorted eg states becoming bands in solids such as perovskite manganese oxides. Because of overlap between metal d,- and O p and py, the d. -/ derived bands are significantly broader. A scheme for such overlap is displayed along the ab plane. 

Kendall K.R., Navas C., Thoams J.K. and zur Loye H.-C., Recent Developments in Perovskite-based Oxide ion Conductors, Solid State Ionics. 82 (1995) pp. 215-223. 

Iwahara, H., Oxide-ionic and protonic conductors based on perovskite-type oxides and their possible applications. Solid State Ionics, 52, 99-104 (1992). 

Kreuer, K.D., Aspects of the formation and mobility of protonic charge carriers and the stability of perovskite-type oxides. Solid State Ionics, 125, 285-302 (1999). 

Larring, Y. and Norby, T., Spinel and perovskite functional layers between Plansee metallic interconnect (Cr-5 wt% Fe-1 wt% Y2O3) in ceramic (Lao 85Sro.i5)o.9iMn03 cathode materials for solid oxide fuel cells, J. Electrochem. Soc., 147, 3251-3256 (2000). 

Kuchynka et al. [125] studied the electrochemical oxidative dimerization of methane to C2 hydrocarbon species using perovskite anode electrocatalysts. Three designs of solid oxide fuel cells were used, including tubular and flat plate solid electrolytes. The maximum current density for the dimerization reaction at these electrocatalysts was related to the oxygen binding energies on the catalyst surface. The anodic reaction was ... 

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