Searching for Low Work Function Perovskite Oxides using Density Functional Theory

摘要

The work function is a crucial parameter for electron emitters used in vacuum electronic devices as lower function allows higher current density and/or lower operating temperature. Perovskite oxides are a novel class of materials for potential use in electron emission applications due to their tunable work functions, robust stability, and good electronic conductivity. In this work, we performed a high-throughput screening based on Density Functional Theory (DFT) simulations and predicted BaMoO3 to be promising emitter materials with low work function, good stability and high electronic conductivity. Our work also provides a general materials design principle governing the work function of perovskites, which is that perovskites with nearly empty electronic d-bands have the lowest work functions.