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arXiv · 2202.04745

A Review of Sc-containing "Scandate" Thermionic Cathodes

Mujan N. Seif·Qunfei Zhou·Xiaotao Liu·T. John Balk·Matthew J. Beck
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Abstract

Although thermionic emission has been studied for more than 100 years, recent interest in novel electron devices for military and civilian use has led to a surge in demand for cathodes with enhanced emission properties (e.g. higher current density, more uniform emission, lower operating temperatures, or extended in-service longevity). Sc-containing "scandate" cathodes have been widely reported to exhibit superior emission properties compared to previous-generation thermionic cathodes, including oxide, B-, and M-type cathodes. Despite extensive study spanning several decades, the mechanism by which the addition of Sc enhances cathode emission remains ambiguous, and certain limitations -- non-uniform emission, low reproducibility, inconsistent longevity -- continue to prevent widespread commercial integration of scandate cathodes into electron devices. This review attempts to survey the literature to-date addressing the fabrication, structure, and properties of scandate cathodes, with particular attention to studies addressing the role of Sc in enhancing emission.

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BibTeXRIS

Mujan N. Seif, Qunfei Zhou, Xiaotao Liu, T. John Balk, Matthew J. Beck. 2022-02-09. A Review of Sc-containing "Scandate" Thermionic Cathodes. https://arxiv.org/abs/2202.04745

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