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Low-Temperature Preparation of Lanthanum Hexaboride Fine Powder via Magnesiothermic Reduction in Molten Salt
K. Bao, C. Liu, B. Yazdani Damavandi, S. Zhang
College of Engineering, Mathematics & Physical Sciences (CEMPS), Harrison Building, University of Exeter, EXETER, EX4 4QF
received August 17, 2016, received in revised form September 20, 2016, accepted October 12, 2016
Vol. 7, No. 4, Pages 403-408 DOI: 10.4416/JCST2016-00057
Abstract
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 (NaCl, KCl and MgCl2) attempted, MgCl2 showed the best accelerating effect. When 20 mol% excessive Mg was used, phase-pure LaB6 particles of ∼ 200 and ∼ 100 nm were obtained respectively after 4 h heating at 1000 °C, and 5 h at 900 °C.
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Keywords
Lanthanum hexaboride, molten salt synthesis, cathode material.
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