Terbium

Terbium is a chemical element with the symbol Tb and atomic number 65. It is a silvery-white, rare earth metal that is malleable, and ductile. The ninth member of the lanthanide series, terbium is a fairly electropositive metal that reacts with water, evolving hydrogen gas. Terbium is never found in nature as a free element, but it is contained in many minerals, including cerite, gadolinite, monazite, xenotime and euxenite. Terbium is used to dope calcium fluoride, calcium tungstate and strontium molybdate in solid-state devices, and as a crystal stabilizer of fuel cells that operate at elevated temperatures. As a component of Terfenol-D (an alloy that expands and contracts when exposed to magnetic fields more than any other alloy), terbium is of use in actuators, in naval sonar systems and in sensors.Most of the world's terbium supply is used in green phosphors. Terbium oxide is in fluorescent lamps and television and monitor cathode-ray tubes (CRTs). Terbium green phosphors are combined with divalent europium blue phosphors and trivalent europium red phosphors to provide trichromatic lighting technology, a high-efficiency white light used for standard illumination in indoor lighting. ATT provides Terbium and compounds at a competitive price, including Terbium Acetate, Terbium Carbonate, Terbium Chloride, Terbium Fluoride, Terbium Hydroxide, Terbium Metal, Terbium Nitrate, Terbium Oxalate, Terbium Oxide, Terbium Sulfate

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Terbium is primarily used in phosphors, particularly in fluorescent lamps and as the high intensity green emitter used in projection televisions, such as the yttrium-aluminum-garnet (Tb:YAG) variety. Terbium responds efficiently in x-ray excitation and is, therefore, used as an x-ray phosphor. Terbium alloys are also used in magneto-optic recording films, such as Tb-Fe-Co. A variety of terbium-doped compounds can act as phosphors for use in television screens, other displays, lighting, or sensors. Most notably, terbium green phosphors are used in trichromatic fluorescent lamps along with europium blue and red phosphors to produce white light with greater energy efficiency than incandescent lighting. In zirconia oxide ceramics, terbium can act both as a light-emitting dopant and a crystal stabilizer, producing a material with excellent structural and optical properties. Other terbium doped compounds have useful electrical properties that make them potentially useful in the semiconductor industry. Terfenol-D is an alloy of terbium, iron, and dysprosium that is magnetostrictive: it contracts or expands when exposed to magnetic fields. This property allows direct conversion between electrical and mechanical power, and the alloy is used in sensors, actuators, and acoustic and ultrasonic transducers, and active noise and vibration cancelling devices. Terbium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity); metals in the form of foil, sputtering target, and rod, and componds as submicron and nanopowder.