Fabrication and electron emission of [Ca₂₄Al_24.08Zr_3.92O₆₄]⁴⁺(4e⁻) electrides

Abstract

Abstract[Ca24Al24.08Zr3.92O64]4+(4e−) electrides are ceramic materials with low work functions that can store high‐density free electrons. So, it has great application potential in electron emission. In this paper, The mixed powders of CaO, Al2O3, ZrO2, and Al in a certain stoichiometric ratio were used as precursors, and [Ca24Al24.08Zr3.92O64]4+(4e−) blocks were fabricated through in‐situ reduction. The synthetic block samples have fewer pores, cracks, and impurities, and the blocks' relative density reaches 99.6%. At the same time, the blocks’ cages were injected with high‐density electrons during the sintering, and the electron density reached 2 × 1021 cm−3. This makes the sample realize the transition from insulation to conductor. In addition, the block's emission current and effective work function is 1.75 A/cm2 and 2.25 eV, respectively, at 1100°C. The research in this paper provides a new way for the low‐cost and industrial production of high‐quality [Ca24Al24.08Zr3.92O64]4+(4e−).