Europium is a chemical element with symbol Eu and atomic number 63. It was isolated in 1901 and is named after the continent of Europe. It is a moderately hard, silvery metal which readily oxidizes in air and water.
Three reasons Europium stands out
- 1
Used as red phosphor in TVs, glows red under UV light.
- 2
It is printed invisibly on euro banknotes as an anti-counterfeiting measure that only fluoresces under ultraviolet light.
- 3
It has the strongest fluorescence of any element, making it invaluable in security and display technology.
The element behind a red pixel
Europium ions emit intense, sharply defined red and blue light when excited. Red phosphors made color television convincing, and modern security inks use the same optical fingerprints. Europium is also unusually willing among lanthanides to form a +2 ion, giving its chemistry a distinctive branch.