# Reduction by thermionic electrons

Certain reduction reactions require electrons as reducing agents. Is the overlapping of orbitals is necessary for electron transfer? I mean if a element $\ce{X}$ is heated and it gives out thermionic electrons then can an oxidizing agent $\ce{Y}$ acquire it and get reduced? If so then will it acquire fast moving electrons or slow moving electrons? What will happen if the inert gas is replaced by $\ce{CO2}$ in an cathode ray tube?