Synthesis and Thermionic Emission Performance of Single Crystals La1-xNdxB6
LI Lulu1, ZHANG Xin1, LIU Hongliang1, ZHANG Fanxing1, XIAO Yixin1, ZHANG Jiuxing1,2
1 Key Laboratory of Advanced Functional Materials of Ministry of Education, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124; 2 School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009
Abstract: The large size high quality La1-xNdxB6(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.
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2017, Vol. 31 
