EUROPIUM (CAS: 7440-53-1)

Europium is a chemical element with the symbol Eu and atomic number 63.

It is named after the continent Europe. It is a moderately hard, silvery metalwhich

readily oxidizes in air and water. Being a typical member of the lanthanide series,

europium usually assumes the oxidation state +3, but the oxidation state +2 is also

common: all europium compounds with oxidation state +2 are slightly reducing.

Europium has no significant biological role and is relatively non-toxic compared to

other heavy metals. Most applications of europium exploit the phosphorescence of

europium compounds.

Application

Relative to most other elements, commercial applications for europium are few and rather

specialized. Almost invariably, they exploit its phosphorescence, either in the +2 or +3

oxidation state.

It is a dopant in some types of glass in lasers and other optoelectronic devices. Europium

oxide (Eu2O3) is widely used as a red phosphor in television setsand fluorescent lamps,

and as an activator for yttrium-based phosphors. Color TV screens contain between 0.5

and 1 g of europium. Whereas trivalent europium gives red phosphors, the luminescence

of divalent europium depends on the host lattice, but tends to be on the blue side. The two

classes of europium-based phosphor (red and blue), combined with the yellow/green terbium 

phosphors give “white” light, the color temperature of which can be varied by altering the

proportion or specific composition of the individual phosphors. This phosphor system is typically

encountered in helical fluorescent light bulbs. Combining the same three classes is one way to make

trichromatic systems in TV and computer screens. Europium is also used in the manufacture of

fluorescent glass. One of the more common persistent after-glow phosphors besides copper-doped

zinc sulfide is europium-doped strontium aluminate.Europium fluorescence is used to interrogate

biomolecular interactions in drug-discovery screens. It is also used in the anti-counterfeiting

phosphors in eurobanknotes.

An application that has almost fallen out of use with the introduction of affordable superconducting

magnets is the use of europium complexes, such asEu(fod)3, as shift reagents in NMR spectroscopy. 

Chiral shift reagents, such as Eu(hfc)3, are still used to determine enantiomeric purity.