Strontium titanate

INTRODUCTION This data sheet summarizes properties of single crystal strontium titanate. 

Transmission Region, (External Transmittance 10% with 2. 0 mm. thickness) 0.39 - 6.8m-  

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PEROXIDES AND PEROXIDE COMPOUNDS - INORGANIC PEROXIDES] (Vol 18) Strontium titanate [12060-52-9]... 

Vemeud (flame fusion) mby, sapphires, and stars spinel mtile strontium titanate... 

For the Verneuil growth of mtile and strontium titanate it is necessary to maintain strongly oxidizing conditions to prevent excessive reduction of TF+ to Tk+. This is achieved by adding a third outer tube carrying extra oxygen to the Verneuil torch (Fig. 1) in the tricone modification. Annealing in O2 at about 1100°C is subsequently used to achieve full oxidation. 

Strontium Titanate. Strontium titanate [12060-59-2], SrTiO, is a ceramic dielectric material that is insoluble in water and has a specific gravity of 4.81. It is made from strontium carbonate and is used in the form of 0.5-mm thick disks as electrical capacitors in television sets, radios, and computers. 

Alkaline-Earth Titanates. Some physical properties of representative alkaline-earth titanates ate Hsted in Table 15. The most important apphcations of these titanates are in the manufacture of electronic components (109). The most important member of the class is barium titanate, BaTi03, which owes its significance to its exceptionally high dielectric constant and its piezoelectric and ferroelectric properties. Further, because barium titanate easily forms solid solutions with strontium titanate, lead titanate, zirconium oxide, and tin oxide, the electrical properties can be modified within wide limits. Barium titanate may be made by, eg, cocalcination of barium carbonate and titanium dioxide at ca 1200°C. With the exception of Ba2Ti04, barium orthotitanate, titanates do not contain discrete TiO ions but ate mixed oxides. Ba2Ti04 has the P-K SO stmcture in which distorted tetrahedral TiO ions occur. 

Historically, materials based on doped barium titanate were used to achieve dielectric constants as high as 2,000 to 10,000. The high dielectric constants result from ionic polarization and the stress enhancement of k associated with the fine-grain size of the material. The specific dielectric properties are obtained through compositional modifications, ie, the inclusion of various additives at different doping levels. For example, additions of strontium titanate to barium titanate shift the Curie point, the temperature at which the ferroelectric to paraelectric phase transition occurs and the maximum dielectric constant is typically observed, to lower temperature as shown in Figure 1 (2). 

Fig. 1. Effect of compositional variations on the dielectric properties of strontium titanate-barium titanate solid solutions. A, BaQ SrQ QTiO B,...

Strontium titanate [12060-59-2] SrTiO, becomes an n-ty e semiconductor when additional electrons are created on the Ti lattice sites by donor doping or when oxygen is removed from the material through heat treatment in a reducing atmosphere. The mobiUty of the electrons in the conduction band is about 6 crc] j(V-s). On the other hand, when ZnO is reduced, 2inc interstitials are formed and these act as donors, each yielding a free electron. 

Figure 4 Raman spectra of a series of strontium titanates showing typicai iine shapes and information avaiiabie for fingerprinting. The broadening of the high-wavenumber lines is related to the polar character of the TiOs octahadra that occur in all of these structures.

Strontium titanate (SrXi03) by reacting titanium isopropoxide and a strontium beta-diketonate complex at 600-850°C and 5 Xorr. 

Strontium titanate (SrTi03) has a large dielectric constant of 12, and a high refractive index with potential opto-electronic applications. It is deposited by MOCVD from titanium isopropoxide and a strontium beta-diketonate complex at 600-850°C and 5 Torr.t" " ... 

Strontium titanate, SrTi03, with a high dielectric constant (310 for single crystal) and high refractive index. 

Fell, W. A., Wessels, B., Tonge, L., and Marks, T., Chemically Vapor Deposited Strontium Titanate Thin Films and Their Properties, Proc. 11th. Int. Conf. on CVD, (K. Spear and G. Cullens, eds.), pp. 148-154, Electrochem. Soc., Pennington, NJ 08534(1990)... 

Wrighton MS, EUis AB, Wolczanski PT, Morse DL, Abrahamson HB, Ginley DS (1976) Strontium titanate photoelectrodes. Efficient photoassisted electrolysis of water at zero Applied Potential. J Am Chem Soc 98 2774-2779... 

Domen, K., Kudo, A., Onishi, T., Kosugi, N., and Kuroda, H., Photocatalytic decomposition of water into hydrogen and oxygen over nickel (II) oxide-strontium titanate (SrTiOj) powder. 1. Structure of the catalysts, ]. Phys. Chem., 90, 292,1986. 

Lehn, J.-M., Sauvage, J.-R, Ziessel, R., and Hilaire, L., Water photolysis by UV irradiation of rhodium loaded strontium titanate catalysts. Relation between catalytic activity and nature of the deposit from combined photolysis and ESCA studies, Isreal ]. Chem., 22,168,1982. 

Figure 14.4. XRD (left) and AFM (right) images of a barium strontium titanate film grown by solution processing.17...

Kaydanova, T. Miedaner, A. Perkins, J. D. Curtis, C. Alleman, J. L. Ginley, D. S. 2007. Direct-write inkjet printing for fabrication of barium strontium titanate-based tunable circuits. Thin Solid Films 515 3820-3824. 

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