Bismuth titanate or bismuth titanium oxide is a solid inorganic compound of

bismuth Bismuth is a chemical element with the Symbol (chemistry), symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental ...

titanium Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in ...

and

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

with the

chemical formula In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, ...

of Bi₁₂TiO₂₀, Bi ₄Ti₃O₁₂ or Bi₂Ti₂O₇.

Synthesis

Bismuth titanate ceramics can be produced by heating a mixture of bismuth and titanium oxides. Bi₁₂TiO₂₀ forms at 730–850 °C, and melts when the temperature is raised above 875 °C, decomposing in the melt to Bi₄Ti₃O₁₂ and Bi₂O₃. Millimeter-sized single crystals of Bi₁₂TiO₂₀ can be grown by the Czochralski process, from the molten phase at 880–900 °C.

Properties and applications

Bismuth titanates exhibit electrooptical effect and

photorefractive effect The photorefractive effect is a nonlinear optical effect seen in certain crystals and other materials that respond to light by altering their refractive index. The effect can be used to store temporary, erasable holograms and is useful for hologr ...

, that is, a reversible change in the

refractive index In optics, the refractive index (or refraction index) of an optical medium is a dimensionless number that gives the indication of the light bending ability of that medium. The refractive index determines how much the path of light is bent, or ...

under applied electric field or illumination, respectively. Consequently, they have potential applications in reversible recording media for real-time

holography Holography is a technique that enables a wavefront to be recorded and later re-constructed. Holography is best known as a method of generating real three-dimensional images, but it also has a wide range of other applications. In principle, i ...

or image processing applications.

References

{{DEFAULTSORT:Bismuth titanate Titanates Bismuth compounds Ceramic materials Piezoelectric materials Ferroelectric materials B

Synthesis

Properties and applications

See also

References