Demarçay, a French chemist, discovered europium in 1896. The metal derives its name from continental Europe. Today, europium is primarily obtained through an ion exchange process from monazite ((Ce,La,Th,Nd, Y)PO4), a mineral rich in rare earth elements. Europium is amongst the least abundant of the rare-earth elements because of its uptake in feldspars.
Europium is also the most reactive of the rare earth elements. It is about as hard as lead, quite ductile and rapidly oxidizes in air. It resembles calcium in its reaction with water; Samples of the metal, even when coated with a protective layer of mineral oil, are rarely shiny and it readily ignites in air above 150°C.
APPLICATIONS OF EUROPIUM
Ceramics and Specialty Glass: Europium has been used to dope some types of glass to make lasers and it is also used as an agent in the manufacture of fluorescent glass.
Phosphors: Europium oxide (Eu2O3) is widely used as a red phosphor in television sets and fluorescent lamps and as an activator for yttrium-based phosphors. Whereas trivalent europium gives red phosphors, the luminescence of divalent europium emits light on the blue side of the visible spectrum.
These two europium phosphors, combined with yellow/green terbium phosphors give "white" light; the colour of which can be varied by altering the proportion or composition of the individual phosphors. Combining the same three phosphors is one way to make trichromatic systems in TV and computer screens. This phosphor system is also used in helical fluorescent light bulbs.
Energy: Europium is being studied for use in nuclear reactors for its significant ability to absorb neutrons.
Science and Medical: Screening for Down's syndrome and some other genetic diseases.
Other Uses: Europium is commonly included in trace element studies in geochemistry and petrology to understand the processes that form igneous rocks, i.e. those rocks that have formed from magmas or lava). It is also used as a phosphor in Euro banknotes to detect their production by counterfeiting.
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