Europium(III) chloride hexahydrate

Europium chloride, also called europium(III) chloride or EuCl3, is a white or yellow solid that belongs to the rare earth metal group. It can decompose into europium(II) chloride (EuCl2) at or below its melting point. Europium chloride displays high water absorption and solubility in water, while the anhydrous form readily dissolves in ethanol. Exposure to humid air causes the anhydrate to absorb water and convert into a white crystalline hexahydrate (EuCl3.6H2O).

Europium(III) chloride hydrate is used as a catalyst in organic synthesis. It is involved in the preparation of amino acid based europium(III) complex in order to prepare photoactive thin films, which finds application in organic light emitting diodes. It is also used as a precursor for the preparation of other europium compounds and its salts.

Europium(III) chloride hexahydrate may be used as a precursor to Eu for the synthesis of lanthanide containing polystyrene beads, which may be used as calibration and internal standards for mass cytometry.

Treating Eu2O3 with aqueous HCl produces hydrated europium chloride (EuCl3·6H2O). This salt cannot be rendered anhydrous by heating. Instead one obtains an oxychloride. Anhydrous EuCl3 is often prepared by the "ammonium chloride route," starting from either Eu2O3 or hydrated europium chloride (EuCl3·6H2O) by heating carefully to 230 °C. These methods produce (NH4)2[EuCl5]:
10 NH4Cl + Eu2O3 → 2 (NH4)2[EuCl5] + 6 NH3 + 3 H2O
EuCl3·6H2O + 2 NH4Cl → (NH4)2[EuCl5] + 6 H2O
The pentachloride decomposes thermally according to the following equation:
(NH4)2[EuCl5] → 2 NH4Cl + EuCl3
The thermolysis reaction proceeds via the intermediary of (NH4)[Eu2Cl7].
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Europium Chloride(13759-92-7) is a widely used raw material for manufacturing phosphors in color cathode-ray tubes and liquid-crystal displays used in computer monitors and televisions. Europium Oxide is a popular red phosphor used in these displays. Additionally, Europium Chloride is also utilized in specialty laser glass. Europium plays a crucial role in energy-efficient fluorescent lighting. It provides not only the required red color, but also the blue color. Many commercially available blue phosphors are based on Europium, making it a fundamental component for color televisions, computer screens, and fluorescent lamps.