Preparations of lanthanum hexaboride (LaB₆) and cerium hexaboride (CeB₆)

Abstract

Due to strong anti-poisoning ability, good emission stability, high emission current density, lanthanum hexaboride (LaB 6 ) and cerium hexaboride (CeB 6 ) have been maturely applied in electron emission emitter. In this paper, a new manufacturing method for LaB 6 (or CeB 6 ) powder was proposed by using La 2 O 3 (or CeO 2 ), B 4 C, and Al as raw materials. After high-temperature reaction in the range of 1673-1773 K and the following alkaline leaching at 90 • C, LaB 6 or CeB 6 powder with particle size of about 10 μm was obtained. Furthermore, by Al metal flux method, the obtained powder was used to manufacture single crystal block with size of several millimeters.

Modification of LaB6 with ZrO2-Al2O3-TiO2 for Improvement of Density and Mechanical and Electrical Properties

“…In 1951, Lafferty identified that LaB 6 possesses excellent hot electron emission properties [1]. Since then, rare earth hexaborides have attracted significant attention from researchers [2,3]. LaB 6 is regarded as an ideal material for electron-emitting cathodes owing to its low work function, high mechanical strength, and chemical stability [4][5][6][7].…”