Low-Temperature Preparation of Lanthanum Hexaboride Fine Powder via Magnesiothermic Reduction in Molten Salt

摘要

Lanthanum hexaboride (LaB6) fine powder was synthesized from La2O3 and B2O3 using a molten-salt-assisted magnesiothermic reduction technique. The effects of salt type, Mg amount, heating temperature and time on the synthesis were investigated, and the relevant reaction mechanisms discussed. Among the three chloride salts (NaCI, KCI and MgCl2) attempted, MgCl2 showed the best accelerating effect. When 20 mol% excessive Mg was used, phase-pure LaB6 particles of similar to 200 and similar to 100 nm were obtained respectively after 4 h heating at 1000 degrees C, and 5 h at 900 degrees C.