Thermionic emission of impregnated dispenser cathodes at low temperature

It has proved that the superior emission capability of a new type impregnated dispenser cathode through impregnates the BaO/SrO/Sc2O3 active substances and covers a mixture W+BaO/SrO/Sc2O3 coating by the pulse laser deposition. However, the thermionic emission of this impregnated dispenser cathode at low temperature is not clear. Our results illustrate that the Current-voltage characteristics of this new impregnated dispenser cathode preserve unsaturated behavior. The maximum of the current density is 2.1 Acm⁻² occurring at 650 °C for the applied voltage from 0 to 3000 V. These results provide hope to further investigate the emission mechanism and make this cathode also applicable for vacuum electron tubes.