SrZrO

One of the first studies of how these secondary phases form was performed by van Roosmalen and Cordfunke. These authors used SEM/EDS and XRD to study postannealed diffusion couples of LSM and YSZ as well as pressed and fired powder mixtures of LSM and YSZ. These experiments showed that reaction products in sufficient quantity to detect by XRD (1—3%) form at temperatures as low as 1170 °C. The two principle reaction products observed were La2Zr207 (LZ) and SrZrOs (SZ), with the relative amount of LZ and SZ depending on the La/Sr ratio in the LSM. Calcia- and baria-doped LaMnOs were found to be similarly reactive with YSZ, and reactivity of LSM with YSZ having 3% or 8% yttria was found to be similar. In the case of the diffusion couples, the layer of reaction products formed at the interface was found (using SEM) to be on the order of 1 /xm after 600 h at 1280 °C and 10—15 fim after 600 h at 1480 °C. By employing Pt diffusion markers... 

Fujimori H, Yashima M, Kakihana M, Yoshimura M (2000) Phase transition and soft phonon modes in SrZrOs around 1200°C by ultraviolet laser Raman spectroscopy. Phys Rev B 61 3971... 

Figure 8.35. A selection of " Zr NMR spectra. A. Stepped-frequency spin-echo spectra of 3 phases of Zr02, adapted from Bastow (1994). B. 14.1 T MAS NMR spectra of Ba and Sr zirconates. Asterisks denote spinning side bands. Note the broader lineshape with possible quadrupolar structure of the more distorted Zr site in SrZrO. From Dec et al. (1993), by permission of the American Chemical Society. C. Static stepped-frequency NMR spectrum of Na2ZrSi05. 1996. D. Stepped-frequency NMR spectrum of Zr metal (lower) with simulated spectrum (upper). 1992. D. Static Zr NMR spectrum of the central transition of A Zr. From Bastow et al. (1992, 1996, 1998b), by permission of the copyright owners.

Herrig and Hempelmann have prepared BaTiOa, BaZrOs, SrTiOs and SrZrOs perovskites by hydrolysis of the corresponding metal alkoxides in a microemulsion system . A strong relationship between the hydrolysis rate and water content of the microemulsion was reported. 

Schober T, Friedrich J, Condon JB. Effective hydrogen diffusivity in SiCeo.95Ybo.o503 a and SrZro.95Ybo.o5Yb0.0503 a. Sohd State Ionics. 1995 77 175-9. 

As-produced material SrCOj-ZrOi mixture calcination (900°C, 1 h) product phase-pure SrZrOs, crystallite size = 19 nm [112],... 

Kobayashi T, Abe K, Ukyo Y and Iwahara H (2000), Reduction of nitrogen oxide by steam electrolysis cell using a protonic conductor SrZro,9Yboi03. and the catalyst Sr/AljOj , Solid State Ionics, 134,241-247. 

Effective chemical diffusivities in the proton conductor, SrZro.95Ybo.05O3. were... 

Slab Models of SrTiOs, SrZrOs and LaMnOs Surfaces. 507... 

The cubic perovskite CaTiOa structure (Fig. 2.10) is more complicated and found as the high-temperature modihcation of different crystals (SrTiOs, BaTiOs, PbTiOs, SrZrOs.PbZrOs). 

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