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Answers : Technology

Does Thermionic emission require vacuum?

Will a hot cathode emit electrons outside of a vacuum? If that won't work, what other ways could I get electrons in a non-vacuum environment? The only thing I can think of is making some plasma and pulling the electrons out electrostaticaly.

2 answers	Answer it!

Jun 22, 2010. 1:58 PM

Re-design says:

IIRC. Thermionic emission will work off any hot metal but it works much more efficiently in a vacuum and without a vacuum the metal tend to burn up much sooner.