Used in catalysts for petroleum refining, especially in fluid catalytic cracking (FCC) processes to improve gasoline yield. Also employed in automotive catalytic converters to reduce emissions by converting carbon monoxide and hydrocarbons into less harmful gases.

Enhances the performance of nickel-metal hydride batteries as a component in hydrogen storage alloys, increasing capacity and lifespan for hybrid vehicles and electronics.

Employed in high-refractive-index glass, such as lanthanum crown glass, for camera lenses, microscopes, telescopes, and optical systems, improving clarity, light transmission, and reducing distortion.

Added to tungsten electrodes for gas tungsten arc welding to enable easier arc starting and greater arc stability.

Utilized in phosphors for fluorescent lamps and LED lighting to produce warm white light, and in specialty lighting like high-brightness halogen lamps to enhance efficiency and extend lifespan.

Plays a role in solid oxide fuel cells as a stabilizer in electrolyte materials, enhancing ionic conductivity at high temperatures. Used in advanced ceramics, including oxygen sensors and high-temperature resistant materials.

In medicine, lanthanum compounds like lanthanum carbonate are used as phosphate binders for patients with chronic kidney disease to effectively lower blood phosphate levels.