Used in the production of yttrium-containing phosphors for color television tubes and LED displays, where it contributes to red and green light emission. Employed in specialty optical coatings due to its high refractive index and transparency in the ultraviolet and infrared ranges, making it suitable for lenses, laser components, and anti-reflective films. Serves as a precursor in the synthesis of other yttrium compounds used in superconductors and ceramic materials. Also utilized in nuclear reactors as a neutron absorber due to its stability and resistance to radiation damage.