Wikipedia Reference Information
Thermionic emission (archaically known as the Edison effect) is the flow of charged particles called thermions from a charged metal or a charged metal oxide surface, caused by thermal vibrational energy overcoming the electrostatic forces holding electrons to the surface. The charge of the thermions (either positive or negative) will be the same as the charge of the metal/metal oxide. The effect increases dramatically with increasing temperature (1000–3000 K). The science dealing with this phenomenon is thermionics.
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