Zero-Dimensional Interstitial Electron-Induced Spin-Orbit Coupling Dirac States in Sandwich Electride

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Chemistry

Background:

• Inorganic electrides offer unique electronic properties due to interstitial electrons.
• Topological states in materials are of significant interest for fundamental science and applications.
• Understanding electron behavior in novel material structures is crucial for discovering new functionalities.

Purpose of the Study:

• To design and characterize a new sandwich electride, 2[CaCl]⁺:2e^-.
• To investigate the topological properties arising from interstitial electrons.
• To evaluate the potential of this electride for catalytic applications, specifically nitrogen (N₂) cleavage.

Main Methods:

• Theoretical design and structural analysis of the 2[CaCl]⁺:2e^- electride.
• Investigation of electronic band structure to identify Dirac points (DPs).
• Calculation of work function (WF) and assessment of catalytic potential for N₂ cleavage using supported ruthenium (Ru).

Main Results:

• A tetragonal lattice structure for 2[CaCl]⁺:2e^- was designed, featuring atomic and interstitial electron layers.
• Nonsymmorphic-symmetry-protected Dirac points (DPs) were identified at X and M points, robust against spin-orbit coupling.
• The electride exhibits a low work function (3.43 eV) and demonstrates outstanding catalytic performance for N₂ cleavage when loaded with Ru.

Conclusions:

• The designed 2[CaCl]⁺:2e^- electride provides a new platform for studying topological states.
• Its unique electronic structure and low work function enable robust electron-supplying characteristics.
• This material shows significant potential for advancing nitrogen (N₂) cracking catalysis.