Widely used as a Lewis acid catalyst in organic synthesis, enabling a variety of transformations such as Friedel–Crafts alkylation, acylation, and Diels–Alder reactions. Its high catalytic efficiency and moisture tolerance make it suitable for reactions in aqueous media. It is particularly effective in promoting glycosylation reactions, which are crucial in carbohydrate chemistry and the synthesis of complex sugars and nucleosides. The compound also finds use in luminescent materials due to the inherent photophysical properties of europium, allowing applications in sensors, imaging, and optoelectronic devices. Additionally, it serves as a dopant in solid-state lasers and phosphors, where it contributes to red emission under UV excitation.