Synthesis and Properties of Single Crystal Ce1-xPrxB6 by Floating Zone Melting

doi:10.15541/jim20140027

Journal of Inorganic Materials ›› 2014, Vol. 29 ›› Issue (10): 1073-1076.DOI: 10.15541/jim20140027

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Synthesis and Properties of Single Crystal Ce_1-_xPr_xB₆ by Floating Zone Melting

ZHANG Fan-Xing¹, ZHANG Xin¹, ZHANG Jiu-Xing¹, LIANG Chao-Long¹, HUANG Ying-Kai²

(1. Key Laboratory of Advanced Functional Materials, Ministry of Education, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China; 2. Van der Waals-Zeeman Institute, University of Amsterdam, Amsterdam Science Park 904, 1098XH, Netherlands)

Received:2014-01-10 Revised:2014-03-19 Published:2014-10-20 Online:2014-09-22
About author:ZHANG Fan-Xing. E-mail: 18810371495@163.com
Supported by:
National Natural Science Foundation of China(50871002);Natural Science Foundation of Beijing(2112007)

Abstract

Abstract:

High-quality single crystals Ce_1-_xPr_xB₆(x = 0.1, 0.2, 0.4) hexaborides were successfully prepared by the reactive spark plasma sintering (SPS) combining with the floating zone melting method using powder of CeB₆ and PrB₆ as raw materials. The thermionic emission properties of the (100) plane of single crystals were investigated. Results show that the (100) plane of Ce_0.8Pr_0.2B₆ single crystal has the maximum emission current density, 66.07 A/cm² at 1873 K, which is higher than the current reported CeB₆single crystal, increased by about 20%. In addition, the thermal emission current density of (100) plane of Ce_0.9Pr_0.1B₆, Ce_0.6Pr_0.4B₆ single crystals are 65.81 A/cm² and 65.31 A/cm², respectively. The (100) plane of Ce_0.8Pr_0.2B₆ single crystal has the lowest work function of 2.61 eV, while the work functions of other single crystals are in the range of 2.64-2.753 eV. Therefore, single crystals Ce_1-_xPr_xB₆ hexaborides have good thermionic emission and low work function, which promises good prospects in the application as a hot cathode material.

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Key words: Ce1-xPrxB6 single crystal, floating zone melting, thermionic emission property

CLC Number:

TQ174

ZHANG Fan-Xing, ZHANG Xin, ZHANG Jiu-Xing, LIANG Chao-Long, HUANG Ying-Kai. Synthesis and Properties of Single Crystal Ce_1-_xPr_xB₆ by Floating Zone Melting[J]. Journal of Inorganic Materials, 2014, 29(10): 1073-1076.

Figures/Tables 6

Fig. 1 Diffraction photographs of second zone melting crystal Ce0.8Pr0.2B6 (a) 360° rapid scanning; (b) slow scanning alone the direction

Fig. 2 Fracture SEM image of the single crystal Ce0.8Pr0.2B6

Fig. 3 Laue picture of single crystal Ce0.8Pr0.2B6 (110) plane

Fig. 4 Rocking curve of Ce0.8Pr0.2B6 (110) plane

Fig. 5 Voltage current characteristic of single crystal Ce1-xPrxB6 (100) plane

Fig. 6 Calculate J0 of single crystal Ce1-xPrxB6 (100) plane

References 11

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Synthesis and Properties of Single Crystal Ce_1-_xPr_xB₆ by Floating Zone Melting

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