Regulating Work Function of [Ca24Al28O64]4+:4e- Electrides Via Changing Solvated Electron Characters.

Since electrides behave as electron donors in catalytic reactions and device substrates due to the anionic electrons localized in periodic interstitial spaces, their work functions (Φ) could be used as key indicators in describing the high electron-donating power. Taking the [Ca24Al28O64]4+:4e- electride as an example, we here propose a new computational scheme of Φ and, further, characterize Φ of the bulk derivative structures of the electride for clarifying the relationship between structural characteristics and Φ. Results indicate that the external strain hardly affects Φ, but the interior heteroatom-doping and distortion bring about significant changes. All these unique variations of the bulk Φ are governed by the distribution and solvation character of anionic electrons in the cage conduction band states. The mechanism of regulating Φ revealed in this work may play a role in the rational design of electride-based catalysts and devices with a superior performance.