The effect of precursor boron nanopowder on the microstructure and emission properties of LaB 6 cathode materials
Abstract Two different structured boron sources have been used for the fabrication of LaB 6 ceramics and their effects on the sintering temperature, microstructure and emission properties were investigated. The results show that the reaction temperature of amorphous boron and La to form LaB 6 is 120...
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Published in | Physica status solidi. C Vol. 9; no. 1; pp. 11 - 14 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
01.01.2012
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Online Access | Get full text |
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Summary: | Abstract
Two different structured boron sources have been used for the fabrication of LaB
6
ceramics and their effects on the sintering temperature, microstructure and emission properties were investigated. The results show that the reaction temperature of amorphous boron and La to form LaB
6
is 1200 °C, which is 150 °C lower than the reaction using crystalline boron. The grain size of LaB
6
prepared by amorphous boron and La is 150 nm, which is much smaller than that of crystalline boron ∼2 μm at the same sintering condition. With the grain size decreasing from 5 μm to 150 nm, the LaB
6
thermionic emission current density increases significantly and the field emission turn‐on field decreases from 1500 V to 1300 V. Using amorphous boron nanopowder can not only enhance the microstructure but also improve the emission properties. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) |
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ISSN: | 1862-6351 1610-1642 |
DOI: | 10.1002/pssc.201084151 |