Phosphors terbium

Sodium terbium borate is used in solid-state devices. The oxide has potential application as an activator for green phosphors used in color TV tubes. It can be used with Zr02 as a crystal stabilizer of fuel cells which operate at elevated temperature. Few other uses have been found. 

The lanthanum phosphate phosphor is usually prepared by starting with a highly purified coprecipitated oxide of lanthanum, cerium, and terbium blended with a slight excess of the stoichiometric amount of diammonium acid phosphate. Unlike the case of the aluminate phosphor, firing is carried out in an only slightly reducing or a neutral atmosphere of nitrogen at a temperature 1000° C. Also this phosphor is typically made with the addition of a flux,... 

There are few uses for terbium. However, terbium can be used as an activator for green phosphor in TV tubes, and some of its compounds are used to produce laser lights. It is also used to dope (coat) some forms of solid-state instruments, as a stabilizer in fuel cells so that they can operate at high temperatures, and as a metal for control rods in nuclear reactors. 

Oxygen-dominant phosphors are made by a solid-state reaction between the intimately mixed components of the phosphor, generally the oxides or oxide forming derivatives, at 500-1500 °C. For instance, Y2Al3Ga20j2 Tb + is made by mixing stoichiometric qnantities of the oxides, containing 5-7 mol% of terbium, with 20% BaFj in ethanol. The mixture is dried and then fired for 2 h at 1500 °C. The resultant flnx is washed with 20% nitric acid. 

Shown in Figure 5 is the emission spectrum for LaOBr.002Tb (23). At these terbium concentrations, the principal emissions occur at 380, 415 and 440 nm which can be used with blue sensitive films. This phosphor is being used in Agfa-Gevaert Co. 

MR screens. In Picker Spectra screens and in the General Electric Co. Blue Max screens. At higher terbium concentrations, the emission spectra emit predominantly green at 542 nm with efficiencies of about 20% comparable to ZnCdS Ag phosphors (24). These green emitting phosphors are suitable for green sensitive films. 

Natural teeth exhibit blue-white fluorescence in the long-wavelength UV [5.435]-[5.437]. Luminescent pigments are used to imitate this phenomena in artificial teeth. They are added to the ceramic paste at a concentration of 0.3-0.5 wt%. Yttrium silicates doped with cerium, terbium, and manganese give the best results [5.438]. The excitation maximum of these phosphors is in the range 325-370 nm. The fluorescence color of the teeth can be varied by changing the concentration of activators. 

Probably the most common use of terbium and its compounds is in phosphors. A phosphor is a material that gives off light when struck by... 

A long list of oxides was prepared sonochemically. Almost all the above-mentioned oxides were synthesized in organic solvents. The other oxides that will be discussed from here on were all prepared in aqueous solutions. Submicron size spheres of silica and alumina prepared by well-known methods were coated sonochemically by nanoparticles of oxides of europium and terbium using the same concentration of ions [81]. We have also used sonochemistry to prepare nanoparticles of silica and alumina doped with the same rare-earth ions for comparison. The highest luminescence intensities were observed for europium and terbium doped in nanoparticles of alumina of dimension 20-30 run. The intensities are comparable or higher than in commercial phosphors. 

Details have appeared of a photovoltaic cell having a high conversion efficiency in which the output efficiency is enhanced by use of a phosphor film containing a terbium bipyridine complex, and of a photorechargeable battery incorporating a conducting polymer of polypyrrole deposited on carbon fibres coated with ferric chloride. The irradiated electrode is thought to possess semiconductor... 

Lai -j Ce TbyP04 exhibit strong green emission radiation. Such kinds of compounds are called phosphors and are used to display color in television. Terbium is also used as an alloy material in compact discs, see also Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Lutetium Neodymium Praseodymium Promethium Samarium Ytterbium. 

EINECS 231-137-6 Terbium. A lanthanide element phosphor activator, dope for solid-state devices, mp = 1356" bp= 3230" d = 8.27. Atomergic Chemetals Cerac Rhdne-Poulenc Sigma-Aldrich Fine Chem. 

Radiation from an aperture lamp is emitted in tight "fan" configuration. For. scanning a sheet of printed paper, it is ideal since the emission is concentrated in a relatively narrow band. Hie phosphor most used for this application is Mg2GKi204 Mn. More recently, some of the terbium activated phosphors like (Mg.CelAlnOigrTb , LaP04 Ce Tb , and Y2SiOg Ce Tb have been employed because the major part of their emission is concentrated in the 543 nm line. 

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