Lanthanum fluoride

Lanthanum fluoride (CAS 13709-38-1), also known as lanthanum trifluoride (LaF₃), is an inorganic rare earth compound combining the optical, electrochemical and tribological properties of the lanthanum series with the stability of metal fluoride salts.

Where is Lanthanum fluoride used?

• Electronics and solar PV: standard precursor for optical thin-film coatings spanning the UV-to-IR range
• Heavy fluoride glass formulations such as ZBLAN, and active membrane material in fluoride ion-selective electrodes for process analytical and quality-control instrumentation
• Mining and metals: electrolysis bath additive and direct precursor in molten-salt electrowinning of lanthanum metal
• Lubricants and metalworking: arc-electrode flux additive and high-temperature solid lubricant whose layered crystal structure provides shear planes effective beyond the practical limit of conventional MoS₂-based systems
• It is registered under REACH in the 10–100 tonnes per annum band.

Good to know: No pharmacopoeial monograph (USP, Ph. Eur.) or food-additive designation applies; supplied exclusively for industrial and technical use. Consult the current Safety Data Sheet — signal word Warning — and applicable workplace exposure regulations before handling.

Commercial specifications

• Purity grades 3N to 5N, expressed on a rare earth oxide basis as La₂O₃/TREO ≥ 99.9 % at the high end, with TREO content quoted separately per trade convention
• Fluorine content typically 28–29 %; oxyfluoride impurity (LaOF) controlled to ≤ 0.2–0.5 % depending on grade
• Physical forms: fine powder in −100 mesh and −325 mesh cuts, granules of 1–3 mm, evaporation tablets, sputter targets
• Pack sizes from 1 kg laboratory quantities up to 25 kg units