Europium (III) Nitrate Hydrate

Europium (III) Nitrate hydrate is a water-soluble, crystalline salt. It appears colorless under natural light, but red under UV light. It is used as a dopant and precursor in the synthesis and production of luminescent, electronic, and optical materials.

Due to its water-solubility, it is easily incorporated into aqueous-based synthetic processes such as hydrothermal and coprecipitation methods. For example, researchers from the University of Malaya, Malaysia used Europium Nitrate as a dopant to prepare Calcium silicates. They compared materials prepared by a hydrothermal process, and a co-precipitation process. Both methods involved incorporating Calcium Nitrate tetrahydrate, Sodium Metasilicate nonahydrate, and Europium (III) Nitrate hydrate in an aqueous solution. The materials have potential applications in bioimaging and biomedicine since they have good biocompatibility and the Europium ions are luminescent.

Europium (III) Nitrate is also used to produce phosphorescent materials. A team of scholars from the University of Montpellier in France designed a rapid and facile synthetic method for creating a phosphor material using a laboratory microwave apparatus. The method is suitable for undergraduate and high school students to perform.  It involves preparing an aqueous solution of various compositions containing Europium (III) Nitrate, Dysprosium (III) Nitrate, Aluminum Nitrate, Calcium Nitrate, and Strontium Nitrate.  Once the nitrates are dissolved, urea is also dissolved in the solution. The beaker of material is covered and subjected to microwave irradiation of 950 W for 3.5 minutes. Upon cooling, the precipitates are collected, crushed, washed with water and ethanol, and then dried at 100 degrees Celsius. The materials glow various colors under UV light depending upon their composition.

Europium (III) Nitrate decomposes to Europium (III) Oxide at elevated temperature.  A group of chemists from the Institute of Chemistry in Beijing, China used this property to prepare a Europium Oxide-Titanium dioxide composite material.  Titanium dioxide-based oxide composites are used in applications such as pigments, anti-reflective coatings, and catalysts. In their work, they dissolved Tetrabutyl titanate and a polymeric surfactant in ethanol.  A dilute solution of Europium (III) Nitrate hydrate dissolved in ethanol was added slowly with careful stirring. The mixture was then subjected to solvothermal treatment in a high-pressure vessel at 120 degrees Celsius for 15 hr. Upon cooling, the precipitates were washed with ethanol and water and dried at 70 degrees Celsius under vacuum. The obtained material emitted red light in photoluminescence experiments.

References

Kee, C. C., Ang, B. C., & Metselaar, H. S. C. (2021). Synthesis of europium-doped calcium silicate hydrate via hydrothermal and coprecipitation method. Ceramics International, 47(4), 4803–4812. https://doi.org/10.1016/J.CERAMINT.2020.10.050

Liu, Z., Zhang, J., Han, B., Du, J., Mu, T., Wang, Y., & Sun, Z. (2005). Solvothermal synthesis of mesoporous Eu2O3–TiO2 composites. Microporous and Mesoporous Materials, 81(1–3), 169–174. https://doi.org/10.1016/J.MICROMESO.2005.01.028

Filhol, J. S., Zitoun, D., Bernaud, L., & Manteghetti, A. (2009). Microwave Synthesis of a Long-Lasting Phosphor. Journal of Chemical Education, 86(1), 72–72. https://doi.org/10.1021/ED086P72