Euro banknotes

These exhibit green, blue, and red luminescent bands under UV irradiation, as a security measure. The red bands are doubtless due to some Eu + complex, probably with a /1-diketonate or some similar ligand. As we have seen, there are Eu + complexes that could cause the green and blue luminescence. Researchers at the University of Twente in the Netherlands suggest that a likely candidate for the source of the green colour is SrGa2S4 Eu +, and that the blue colour may be caused by (Ba0)j .6Al203 Eu +. It s quite appropriate that Euro notes contain europium, really. 

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In 2000, most European countries switched from their traditional currencies to the euro. Lanthanide luminescence is used as a means of preventing counterfeit euro banknotes from passing into the money chain. Excitation of euro banknotes with ultraviolet light results in fluorescence in the red, green and blue regions due to complexes of europium (Eu3+), terbium (Tb3+) and thulium (Tm3+), respectively, that are present in the banknotes. 

Bones, J. Macka, M. Pauli, B. Evaluation of monolithic and sub 2 p,m particle packed columns for the rapid screening for illicit drugs—Application to the determination of drug contamination on Irish euro banknotes. Analyst 2007,... 

Europium is certainly the most versatile lanthanide. Its luminescence can be used to reproduce blue (BaMgAlioOn Eu +), green (SrGa2S4 Eu +), or red (any sensitized Eu + complex). The presence of such europium compounds in the luminescent inks used on the euro banknote is suspected for the blue and the green luminescent colors, undoubted for the red-emitting one. Eu + is produced and stabilized in phosphors under reducing atmospheres. 

Europium(ni) oxide Widely used as a red phosphor in television sets and fluorescent lamps, and as an activator for yttrium-based phosphors. Europium photoluminescence is used in the anti-coimterfeiting phosphors in Euro banknotes. Red phosphorescent material. 

With the introduction of the Euro in 2002, this subject is very topical and should therefore be particularly mentioned within the context of security printing. For security reasons, banknotes may only be printed by so-called " government printers" and state-licensed printers. 

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