Highly efficient photoelectric effect in halide perovskites for regenerative electron sources

Electron sources are a critical component in a wide range of applications such as electron-beam accelerator facilities, photomultipliers, and image intensifiers for night vision. We report efficient, regenerative and low-cost electron sources based on solution-processed halide perovskites thin films when they are excited with light with energy equal to or above their bandgap. We measure a quantum efficiency up to 2.2% and a lifetime of more than 25 h. Importantly, even after degradation, the electron emission can be completely regenerated to its maximum efficiency by deposition of a monolayer of Cs. The electron emission from halide perovskites can be tuned over the visible and ultraviolet spectrum, and operates at vacuum levels with pressures at least two-orders higher than in state-of-the-art semiconductor electron sources.

Fangze Liu, Siraj Sidhik, Mark A. Hoffbauer, Sina Lewis, Amanda J. Neukirch, Vitaly Pavlenko, Hsinhan Tsai, Wanyi Nie, Jacky Even, Sergei Tretiak, Pulickel M. Ajayan, Mercouri G. Kanatzidis, Jared J. Crochet, Nathan A. Moody, Jean-Christophe Blancon, Aditya D. Mohite