Used in fiber optics to enhance the refractive index of glass, enabling efficient transmission of light signals over long distances. Commonly applied in the production of optical fibers for telecommunications and internet infrastructure. Also utilized as a catalyst in polymerization reactions, especially in the manufacture of polyethylene terephthalate (PET) plastics. Employed in infrared optics due to its transparency in the infrared range, making it suitable for lenses and windows in thermal imaging devices. Investigated for use in semiconductor applications and certain types of solar cells to improve efficiency.