Electron emission mechanism of scandium-tungsten cathodes

被引：7

作者：

Cheng, Yin ^{[1
,2
]}

Sun, Yuan ^{[1
]}

Zhou, Yizhou ^{[1
]}

Wang, Shiyang ^{[1
]}

Meng, Jie ^{[1
]}

机构：

[1] Chinese Acad Sci, Shi Changxu Innovat Ctr Adv Mat, Inst Met Res, Shenyang 110016, Peoples R China

[2] Univ Sci & Technol China, Sch Mat Sci & Engn, Shenyang 110016, Peoples R China

来源：

INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS | 2022年 / 105卷

关键词：

Thermoelectric materials; Crystal structure; Electronic structure; Density functional theory; First-principle calculations;

D O I：

10.1016/j.ijrmhm.2022.105828

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Scandium-tungsten (Sc-W) cathodes have garnered a lot of research attention due to their high emission current density. This study investigates the electronic properties of Sc-W cathodes using the VASP code to explain the operating mechanism of hot electron emission. The results reveal that the work function is decreased by 0.58 eV, whereas the charge density in the crystal structure, the number of high valence electrons and the energy of electrons increase when Sc content is increased from 1% to 2%. Moreover, the bandgap and energy required for electrons to jump from the valence band to the conduction band decreased with the increase of Sc content, enhancing the current emission density and reducing the work function of the cathode.

引用

页数：5

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