First principles study on stability and hydrogen adsorption properties of Mg/Ti interface

Area of Science:

• Materials Science
• Computational Chemistry
• Hydrogen Storage

Background:

• Magnesium (Mg) and titanium (Ti) interfaces are crucial for hydrogen storage applications.
• Understanding interfacial stability and hydrogen interaction is key to optimizing material performance.

Purpose of the Study:

• To investigate the hydrogenation and stability of the Mg/Ti interface using first-principles calculations.
• To identify stable interface configurations and analyze hydrogen adsorption behavior.
• To explore the potential of Ti insertion for enhancing Mg-based hydrogen storage.

Main Methods:

• First-principles calculations were employed to simulate the Mg/Ti interface.
• Lattice strain and ion movement were imposed to determine stable configurations.
• Hydrogen adsorption energies and electronic structures were analyzed.

Main Results:

• The anti-symmetrical Mg/Ti interface configuration was identified as the most stable.
• A low-energy pathway for configuration transition was found.
• A highly favorable hydrogen adsorption energy of -0.991 eV was observed at the interface's top site.
• Titanium was found to act as a hydrogen capturer, indicating strong H-Ti and H-Mg interactions.

Conclusions:

• The Mg/Ti interface, particularly the anti-symmetrical configuration, offers enhanced thermodynamic stability for hydrogen adsorption.
• Inserting Ti layers creates a stable interfacial zone for hydrogen, significantly improving the hydrogen storage capacity of Mg.
• These findings suggest a promising strategy for developing advanced Mg-based hydrogen storage materials.