Synthesis barium titanate

K. Osseo-Asare, F. J. Arriagada, and J. H. Adair, "Solubility Relationships in the Coprecipitation Synthesis of Barium Titanate Heterogeneous Equihbria in the Ba—Ti—C2O4—H2O System," in G. L. Messing, E. R. Fuller, Jr., and Hans Hausin, eds.. Ceramic Powder Science Vol. 2,1987, pp. 47-53. 

D. Miller, J. H. Adair, W. Huebner, and R. E. Newnham, "A Comparative Assessment of Chemical Synthesis Techniques for Barium Titanate," Paper, 88th Annual Meeting of the American Ceramic Society, Pittsburgh, Pa., April 27—30, 1987. 

The most significant commercial product is barium titanate, BaTiO, used to produce the ceramic capacitors found in almost all electronic products. As electronic circuitry has been rniniaturized, demand has increased for capacitors that can store a high amount of charge in a relatively small volume. This demand led to the development of highly efficient multilayer ceramic capacitors. In these devices, several layers of ceramic, from 25—50 ]lni in thickness, are separated by even thinner layers of electrode metal. Each layer must be dense, free of pin-holes and flaws, and ideally consist of several uniform grains of fired ceramic. Manufacturers are trying to reduce the layer thickness to 10—12 ]lni. Conventionally prepared ceramic powders cannot meet the rigorous demands of these appHcations, therefore an emphasis has been placed on production of advanced powders by hydrothermal synthesis and other methods. 

Ihlefeld, J. F. Borland, W. Maria, J. P. 2005. Synthesis and properties of barium titanate thin film on copper substrates. In Ferroelectric Thin Films XIII, edited by Ramesh, R. Maria, J. P. Alexe, M. Joshi, V. Mat. Res. Soc. Symp. Proc. 902 7-14. 

Some examples of application of metal alkoxides for synthesis of ferroe-lectrics such as BaTi03-based materials, complex niobates and tantalates, PZT andPLZT-materials, and high-temperature superconductors are discussed below. 10.1. Barium titanate and BaTiOj-based solid solutions... 

Barium titanate and BaTi03-based materials are most commonly used for ceramic capacitors with high dielectric permittivity. BaTi03 powder of extremely high quality (in respect of its purity, stoichiometry, particles morphology) is required for most of the modem applications. This characteristic may be considerably improved by the application of alkoxide precursors. Thus, it is of no surprise that synthesis of BaTi03 and BaTi03-based materials from metal alkoxides attracted considerable attention for several decades. The first works on... 

Hydrothermal synthesis is being increasingly adopted for the commercial production of compositionally tailored barium titanates for MLCCs. 

Barium titanate. The synthesis of barium titanate on the basis of HTD and barium dioxide was reported in [53]. The following reactions were studied ... 

Fig. 6.14 shows X-ray diffraction patterns of the products obtained after activation of the mixtures of Ba02 with rutile, anatase and metatitanium acid. It follows, that mechanochemical synthesis of barium titanate occurs only if anatase and metatitanium acid are used as initial reagents. The presence of barium carbonate phase was observed for all the products. For the mixture with anatase, the amount of barium carbonate increases with activation time, and for the mixture with metatitanium acid it... 

Avvakumov E.G., Sysoev B.E., Kosova N.V. The role of hydrolytic interactions in solid-phase mechanical synthesis of barium titanate. Proc. of Ail-Union Conf. Mechanochemical Synthesis . Vladivostok, August 20 - 23, 1990. 

The inverse-micelle approach may also offer a generalized scheme for the preparation of monodisperse metal-oxide nanoparticles. The reported materials are ferroelectric oxides and, thus, stray from our emphasis on optically active semiconductor NQDs. Nevertheless, the method demonstrates an intriguing and useful approach the combination of sol-gel techniques with inverse-micelle nanoparticle synthesis (with OTO erafe-temperature nucleation and growth). Monodisperse barium titanate, BaTiOs, nanocrystals, with diameters controlled in the range from 6-12nm, were prepared. In addition, proof-of-principle preparations were successfully conducted for Ti02 and PbTiOs. Single-source alkoxide precmsors are used to ensure proper stoichiometry in the preparation of complex oxides (e.g. bimetallic oxides) and are commercially available for a variety of systems. The... 

J Synthesis and Modification of Submicron Barium Titanate Powders... 

Anuradha, T.V., Ranganathan, S., Mimani, T., and Patil, K.C., Combustion synthesis of nanostructured barium titanate, Scripta Mater., 44, 2237, 2001. 

Blanco-Lopez, M.C., Rand, B., and Riley, RL., J. Ear. Ceram. Soc., 17, 281,1997. Lu, S., Lee, B.I., and Wang, Z., Synthesis of redispersible nano-sized barium titanate powders by hydrothermal method, in Ceramic Transactions, vol. 106, Dielectric Materials Devices, edited by K.M. Narr and A.R. Bhalla, American Ceramic Society, Westerville, OH, 2000. 

With the exceptions of quartz and emerald, the typical crystals grown hydrothermally are small. There is no inherent reason for this. Hydrothermal synthesis of fine powders of barium titanate and similar dielectric materials is of importance in capacitor manufacture. 

Synthesis and Dispersion of Barium Titanate and Related Ceramic Powders... 

Phule, D. P., and Risbud, S. H., Sol-gel synthesis of barium titanate powders using barium acetate and titanium(IV) isopropoxide, Adv. Ceram. Mat., 3, 183 (1988). 

S, O Brien, L, Bras, and C, B, Murray. Synthesis of monodisperse nanoparticles of barium titanate Toward a generalized strategy of oxide nanoparticle synthesis. J. Am. Chem. Soc.,... 

J, J, Urban, W, S, Yun, Q, Gu, and H. Park. Synthesis of single-crystaUine perovskite nanorods composed of barium titanate and strontium titanate. J. Am. Chem. Soc., 124 ... 

Novak, Z., Knez, Z., Ban, L, Drofenik, M., 2001, Synthesis of barium titanate using supercritical COj drying, J. Supercrit. Fluids 19, 209-215. 

W.-N. Wang, I. W. Lenggoro, Y. Terashi, Y. C. Wang, K. Okuyama Direct synthesis of barium titanate nanoparticies via a low pressure spray pyrolysis method, J. Mater. Res. 20 (10), 2873-2882 (2005b). 

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