Al atom on MoO3(010) surface: adsorption and penetration using density functional theory

Area of Science:

• Materials Science
• Computational Chemistry
• Nanotechnology

Background:

• Understanding interfacial phenomena is crucial for nanothermite ignition and reaction mechanisms.
• The Al/MoO3 nanothermite system's interfacial interactions require detailed investigation.

Purpose of the Study:

• To model the Al/MoO3 interface using first-principle density functional theory.
• To investigate the adsorption and subsurface-penetration of aluminum adatoms on MoO3.
• To elucidate the initiation of interfacial interactions in Al/MoO3 nanothermites.

Main Methods:

• Utilized first-principle density functional theory (DFT) calculations.
• Modeled an aluminum adatom on a MoO3(010) slab.
• Tracked adsorption energies and penetration barriers for various configurations.

Main Results:

• Aluminum adatoms spontaneously penetrate the topmost atomic plane of MoO3(010).
• The most stable adsorption site is a 4-fold hollow site below the surface.
• A low energy barrier (0.2 eV) facilitates subsurface penetration, indicating potential atomic intermixing.

Conclusions:

• Subsurface penetration of Al into MoO3 is energetically favorable.
• The Al/MoO3 interface likely involves intermixing of Al, Mo, and O atoms.
• Findings offer new insights into Al/MoO3 interfacial interactions and nanothermite ignition mechanisms.