Direct atomic imaging and density functional theory study of the Au24Pd1 cluster catalyst

Area of Science:

• Materials Science
• Nanotechnology
• Catalysis

Background:

• Gold-palladium (Au-Pd) clusters are crucial in catalysis.
• Understanding their atomic structure is key to optimizing performance.
• Previous studies lacked direct atomic-resolution imaging of such clusters.

Purpose of the Study:

• To directly image the atomic structure of calcined Au24Pd1 clusters.
• To determine the low-energy configurations of Au24Pd1 clusters using computational methods.
• To investigate the electronic interactions between gold and palladium within the clusters.

Main Methods:

• Aberration-corrected scanning transmission electron microscopy (STEM) for atomic imaging.
• Gold atoms as mass standards for precise cluster size determination.
• Density-Functional/Basin-Hopping (DFTBH) computational algorithm for structural modeling.

Main Results:

• Direct atomic-resolution imaging confirmed cluster size as 25 ± 2 atoms.
• Computational modeling identified favored cage structures with palladium at the core.
• Electron transfer analysis indicated palladium acts as an electron promoter for gold.

Conclusions:

• Atomic-resolution imaging and computational methods provide a comprehensive understanding of Au24Pd1 cluster structure.
• The identified structural and electronic properties suggest potential for enhanced catalytic activity.
• Palladium's role as an electron promoter highlights its importance in designing advanced gold-based catalysts.