Scandium fluoride

Scandium fluoride (CAS 13709-47-2), also referred to commercially as scandium trifluoride (ScF₃), is an anhydrous crystalline ionic solid belonging to the rare earth elements category.

Where is Scandium fluoride used?

• Mining and metals processing: principal intermediate for scandium metal production and aluminium–scandium master alloy manufacture
• Metallothermic (aluminothermic) reduction and fluoride electrolysis: high-purity ScF₃ as starting material, where fluoride content and low impurity profiles influence yield and alloy quality
• Electronics and solar PV: UV and deep-UV optical thin-film coatings, exploiting wide bandgap and low refractive index for anti-reflection and high-reflectance multilayer stacks
• Laser host crystal precursor and ceramic capacitor materials, where dimensional stability under thermal cycling is critical
• Aerospace and defence: physical vapour deposition (PVD) processes, including magnetron sputtering
• It is also used in optical coating and alloy reduction.

Good to know: Classified as an acutely toxic solid (UN 3288, Class 6.1, signal word: Danger); handling requires engineering controls, respiratory protection, and segregation from incompatible materials. No standard pharmacopoeial monograph (USP, Ph. Eur.) or food-grade designation applies; no FEMA flavour or E-number status is relevant.

Commercial specifications

• TREO typically exceeding 81 %
• Purity grades on a rare earth oxide basis: ScF₃/TREO at 99.9 %, 99.99 %, and 99.999 %
• Forms: fine powder, 3–12 mm vacuum-deposition pieces, and sputter targets
• Lot sizes 100 g to 1 kg, packaged under dry-atmosphere conditions to prevent hydrolysis