Photoelectron emission from Cs3Sb coated on a cathode tip

► We developed an equipment to coat photoemissive material on a small area of a cathode tip for TEM in high vacuum and to detect photoelectrons from coated material. ► Cs3Sb emitting photoelectrons was formed at −20 °C from the layers of Sb, Cs and Sb which were deposited on a cathode tip at −20 °C with the developed equipment. ► Lifetime tests of Cs3Sb photocathode were performed at −20 °C and 11 °C. ► The effects of vacuum level, temperature and anode voltage on photoemission from Cs3Sb were also examined.