La1-xNdxB6单晶的制备及热电子发射性能*

doi:10.11896/j.issn.1005-023X.2017.018.005

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Abstract The large size high quality La_1-xNd_xB₆(x=0.1-0.3) single crystals had been successfully prepared by floating zone melting method using powder of LaB₆ and NdB₆ as raw materials. We investigated the thermionic emission performance of (100) plane of single crystals. The single crystals length was more than 40 mm and the diameter was greater than 4 mm.The single crystal tests of diffraction photographs, Laue pattern, rocking curves and fracture SEM images showed that the single crystals’ qua-lity was very high. The thermionic emission results showed that with the increase of Nd content, the null field thermionic emission current density decreased from 6.01 A/cm² to 4.83 A/cm² at 1 873 K, 4 000 V and the average of effective work function increased from 2.88 eV to 2.95 eV.

Key words： La_1-xNd_xB₆ single crystal thermionic emission floating zone melting rare earth hexaboride

Published: 25 September 2017 Online: 2018-05-08

CLC number:

TQ174

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	Articles by authors
	LI Lulu
	ZHANG Xin
	LIU Hongliang
	ZHANG Fanxing
	XIAO Yixin
	ZHANG Jiuxing

Cite this article:

LI Lulu,ZHANG Xin,LIU Hongliang, et al. Synthesis and Thermionic Emission Performance of Single Crystals La_1-xNd_xB₆[J]. Materials Reports, 2017, 31(18): 21-24.

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https://www.mater-rep.com/EN/10.11896/j.issn.1005-023X.2017.018.005 OR https://www.mater-rep.com/EN/Y2017/V31/I18/21

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