Absolute emission current density of O− from 12CaO⋅7Al2O3 crystal

Abstract

Strong and high purity O− negative ion emission has been observed from a synthesized crystal 12CaO⋅7Al2O3 surface. A μA/cm2-level O− emission from this material has been achieved at the surface temperature of 800 °C and the extraction field over 1000 V/cm, which is about three orders of magnitude higher than the current density emitted from the Y2O3-stabilized ZrO2 electrolyte surface. The strong emissivity of this material, as well as easy and economical fabrication, may provide a useful tool to generate the O− negative ion, which is expected to be one of the most important radicals for chemical syntheses and material modifications.