Used as a key component in phosphors for color television screens and LED lighting, enabling bright red and green emissions. Employed in ceramics and glass to improve thermal stability and resistance to cracking at high temperatures. Serves as a host material for rare-earth dopants in solid-state lasers and optical coatings. Applied in electronics as a gate dielectric in thin-film transistors due to its high dielectric constant. Utilized in medical imaging and cancer treatment when doped with radioactive isotopes for targeted radiation therapy. Also used in corrosion-resistant coatings for aerospace components and in fuel cells as a stabilizer for zirconia electrolytes.