Breaking Molecular Nitrogen under Mild Conditions with an Atomically Clean Lanthanide Surface

Area of Science:

• Materials Science
• Inorganic Chemistry
• Surface Science

Background:

• Molecular nitrogen (N₂) is abundant but inert, posing challenges for its chemical activation.
• Developing methods for nitrogen fixation under mild conditions is crucial for various industrial and environmental applications.

Purpose of the Study:

• To demonstrate a novel method for breaking molecular nitrogen (N₂) under mild conditions.
• To investigate the growth and properties of lanthanide nitride thin films.
• To explore the reversibility of nitrogen incorporation into lanthanide nitrides.

Main Methods:

• Evaporation of lanthanides in a partial N₂ atmosphere at room temperature and low pressure (10^-4 Torr).
• X-ray diffraction (XRD) for structural confirmation of lanthanide nitride thin films.
• In situ conductance measurements to monitor surface and bulk reactions.

Main Results:

• Successful growth of lanthanide nitride thin films under mild conditions.
• Observation of immediate surface and slower bulk reactions upon exposure of lanthanide films to N₂ gas.
• Demonstration of partial reversal of nitrogen incorporation by cycling vacuum and N₂ conditions.

Conclusions:

• Lanthanide films can facilitate the cracking and incorporation of molecular nitrogen (N₂) under mild conditions.
• The process allows for the synthesis of lanthanide nitride thin films with potential for reversible nitrogen storage.