Perovskite thin films

Schwartz, R. W. 1997. Chemical solution deposition of perovskite thin films. Chem. Mat. 9 2325-2340. 

Kato, K. Zheng, C. Dey, S. K. Torii, Y. 1997. Chemistry of the alkoxy-derived precursor solutions for layer-structured perovskite thin films. Int. Ferro. 18(l-4) 225-235. 

As yet, more work is also required to gain insight in the role of the ceramic microstructure in the performance values of membranes, and to evaluate different processing routes for the fabrication of perovskite thin films. 

Abstract LaCrOs based perovskites thin films are a prospective material as a protective... 

Dawber, M. and Scott, J.F. (2000) A model for fatigue in ferroelectric perovskite thin films. Appl. Phys. Lett., 76,1060-1062 and 3655. 

Mutoro E, Crumlin EJ, Biegalski MD, Christen HM, Shao-Hom Y (2011) Enhanced oxygen reduction activity on surface-decorated perovskite thin films for solid oxide fuel cells. Energ Environ Sci 4 3689... 

Kg. 12 Raman spectra of stainless steel (a) before treatment and (b) after treatment and annealing at 700 "C with LaCr03 perovskite thin film, (c) Raman spectra of LaCrOj coatings annealled at various temperatures. Figure reproduced from reference [126]. 

The hydrothermal method to synthesize perovskites thin films and powders has a number of advantages, such as high purity and high quality of the product. In order to promote hydrothermal reactions, Ohta et al. [57] developed an ultra-sonic-assisted hydrothermal method and confirmed that it produces dense and thick lead zirconate titanate (PZT) films. For this film, ultrasonic irradiation was used from the beginning of the reaction for 18h, followed by a 6h deposition without ultrasonic irradiation. These results indicate that the ultrasonic irradiation mainly promotes the nucleation process and during the ultrasonic irradiation, the number of grains increases. 

Phani, A.R., Passacantando, M., and Santucci, S. (2007) Synthesis of nanocrystalline ZnTiOs perovskite thin films by sol-gel process assisted by microwave irradiation. /, Phys. Chem. Solids, 68, 317-323. 

Post, M.L., and B.W. Sanders, 1993, Oxygen sensing irsing the bulk properties of perovskite thin-films, in Proc. Symp. on Chemical Sensors II, 1993, eds M. Butler, A. Ricco and N. Yamazoe (Electrochemical Society, Pertrrington) pp. 358-362. 

The heating rate of the thermal annealing used for the crystallization of the amorphous layer has a strong effect on the heterostructural characteristics of the crystalline film and therefore on the electrical properties. Figure 27.13 shows the Rutherford backscattering spectroscopy (RBS) spectra of two (Ca, Pb)Ti03 perovskite thin films prepared from the same precursor solution, but annealed at 650 °C with a relatively slow ( 8°Cs ) and a rapid ( 30°Cs ) heating rate. 

Stresses produced in sol-gel-derived films modify the lattice parameters of the film and its orientation or texture. These effects are clearly observed in the X-ray diffraction (XRD) patterns of Figure 27.16 [55]. The XRD pattern of a (Ca, Pb) TiOs perovskite thin film on a Pt-coated silicon substrate shows a textured film with a (100) preferred orientation and with the cell parameters for the perovskite indicated in Table 27.5. When this film is electrolytically separated from the substrate, it recovers the random orientation of the ceramic powder and its preferred orientation disappears observe the lattice parameters and strains measured in a (Ca, Pb)TiOs thin film on the substrate and this film is separated from the substrate in comparison with those of the bulk ceramic (Table 27.5) [55]. 

Figure 27.19 (Ca, PblTiOs perovskite thin films on two different substrates promoting the preferred orientation of the perovskite by the mismatch between the lattice parameters of the perovskite and those of the substrate surface, (a) The perovskite film on a substrate prepared with a (11 llRsTi template layer on a R-coated silicon substrate. Inset shows the...

Ref. [78].) It corresponds to a PZT perovskite thin film on a flexible polylmide substrate that was deposited from sol-gel precursors and crystallized at temperatures below 350 °C. 

Fig. 14.6 (a) SEM cross section image of the perovskite thin film on Pd substrage (b) X-ray diffraction pattern of the perovskite thin film on Pd substrate... 

Electrically Tunable Dielectric and Conduction Properties in Perovskite Thin Films... 

Generally, the perovskite thin films are integrated in capacitor configuration for these applications. In most practical cases the tunability of the capacitance... 

According to the above discussions, the dielectric tunable properties of perovskites are highly associated with the phase transition of ferroelectrics, crystal texture, and lattice anharmonic interactions. These accordingly provide us approaches to enhance the tunable properties of perovskites thin films. 

G.J. la O et al.. Catalytic activity enhancement for oxygen reduction on epitaxial perovskite thin films for solid-oxide fuel cells. Angew. Chem.-lntl. Ed. 49, 5344-5347 (2010)... 

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