Photoemission is a process in which photons are converted into free electrons. Photocathodesare the typical materials for the process. They emit electrons when a light is irradiated upon. Thetraditional method of manufacturing photocathodes is complicated, requires specialized equipment, and islimited very small sized samples. Cs3Sb photocathode was formed on a substrate in   atmosphericconditions. The photocathode formation was a gas phase reaction with the substrate. Vacuum deviceswere made to test electron emission characteristics of the formed photocathode. Visible light ofwavelength 475 nm was used for the primary light source. The results showed high current density andlong term stability of the photoelectron emission.