Europium-doped yttrium oxide

Cates, M.R. Allison, S.W. Franks, L.A. Borella, H.M. Marshall, B.R. Noel, B.W. Laser-induced fluorescence of europium-doped yttrium oxide for remote high-temperature thermometry. Proc. Laser Inst. Am. 1985, 142, 49-51. 

The complex Yo.99Euo.oi(N2H3COO)3-3H20 decomposes in air at 600 °C to form the corresponding europium-doped yttrium oxide. The decomposition temperature can be reduced, however, by mixing the redox compound with a calculated amount of either ammonium nitrate (1 6) or ammonium perchlorate (1 2.4) and rapidly heating the mixture at 300 °C to obtain Eu -substituted Y2O3 - the red phosphor. 

Europium oxide is now widely used as a phospor activator and europium-activated yttrium vanadate is in commercial use as the red phosphor in color TV tubes. Europium-doped plastic has been used as a laser material. With the development of ion-exchange techniques and special processes, the cost of the metal has been greatly reduced in recent years. 

The cathodoluminescence of thin films containing rare-earth oxides was studied by Hansen and Myers (140). Films of yttrium oxide doped with rare earths were prepared in vacuum by electron-bombardment evaporation of the oxide powder mixtures. Luminescent rise and decay curves were obtained for activation with europium, gadolinium, terbium, and dysprosium. 

Europium has not many applications. Commercial applications of europium almost always take advantage of the phosphorescence, either in the 2+, or 3+ oxidation state. Industrial application started in the 1960s (Wickersheim and Lefever 1964). Many advances have been made since, leading to the discoveiy of europium activated yttrium oxysulfide (YaOaSiEu " ). This is a red phosphor. Other main industrial phosphors doped with europium are Sr5(P04)3Cl Eu and BaMgAliiOiviEu " for blue, and Y203 Eu " for red. Green phosphors involve terbium (Tb (Caro 1998 Nazarov et al. 2004). The phosphors are for instance used in flat screen monitors and televisions. 

Yttrium alloys have many applications. The metal doped with rare earths such as europium is used as phosphor for color television receivers. When added to iron, chromium, vanadium, niobium, and other metals it enhances resistance of these metals and their alloys to high temperature oxidation and recrystallization. It is a deoxidizer for vanadium and other nonferrous metals. Yttrium-aluminum garnets are used in lasers and in jewelery gemstones. Yttrium-iron garnets are used as transmitters and as transducers of acoustic energy. 

In a similar work, ultrasound radiation was used to prepare EU2O3 doped in zir-conia and yttrium-stabilized zirconium (YSZ) nanoparticles [83]. Europium oxide was also coated sonochemically on the surface of submicron spherical zirconia and YSZ, which were fabricated by wet chemical methods. Time decay measurements of the doped and coated materials were conducted using a pulsed laser source. Lifetimes < 1.1 ms radiative lifetime of the Eu+ ions were detected for the doped and coated as-prepared materials. When the doped and coated samples were an-... 

Europium is the most reactive of the rare earth metals. It is quickly oxidized in air and ignites at about 150°C. Yttrium oxysulfide, doped with europium, is used in phosphors to give red colors in television screens. 

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