thermionic work function
Quick Summary
The thermionic work function is the energy needed to remove an electron from a heated metal surface. This is a specific type of electronic work function, which is the general energy required to free an electron from a metal. Thermionic emission occurs when heat provides electrons with enough energy to overcome the attractive forces within the metal.12
The value of the thermionic work function varies by material and surface condition. Typical values for metals range from two to five electron volts. This phenomenon is crucial for applications like electron tubes and thermionic power converters, which convert heat directly into electricity. The rate of electron emission increases significantly with temperature and decreases with a larger work function.2134
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