Oxidation of Al doped Au clusters: a first principles study

Area of Science:

• Computational chemistry
• Materials science
• Surface science

Background:

• Gold clusters are of interest for catalysis and nanotechnology.
• Doping with other elements can tune cluster properties.
• Understanding oxidation mechanisms is crucial for practical applications.

Purpose of the Study:

• To investigate the structural and stability properties of aluminum-doped gold clusters.
• To explore the oxidation mechanism of these doped clusters with molecular oxygen.

Main Methods:

• First-principles calculations using density functional theory (DFT).
• Plane-wave pseudopotential approach with generalized gradient approximation (GGA).
• Analysis of binding energy, energy differences, and frontier molecular orbital gaps.

Main Results:

• Aluminum substitution promotes early three-dimensional structures in gold clusters.
• Au(3)Al and Au(5)Al clusters show exceptional stability.
• Oxidation proceeds via a dissociative mechanism with charge transfer from Al to Au.

Conclusions:

• Aluminum doping significantly alters the structural and electronic properties of gold clusters.
• The preferential interaction of oxygen with aluminum sites dictates the oxidation pathway.
• These findings provide insights into the design of novel catalytic materials.