Enhanced sputtering yields from single-ion impacts on gold nanorods

Area of Science:

• Materials Science
• Surface Science
• Nanotechnology

Background:

• Sputtering is a key process in thin film deposition and surface modification.
• Understanding sputtering yields is crucial for optimizing material processing.
• Nanostructured materials exhibit unique surface properties compared to bulk materials.

Purpose of the Study:

• To investigate the sputtering yields of monocrystalline gold nanorods under ion irradiation.
• To quantify the enhancement in sputtering yields compared to flat surfaces.
• To elucidate the underlying mechanisms responsible for the observed sputtering enhancement.

Main Methods:

• Experimental irradiation of gold nanorods using 80 keV Xenon (Xe) ions.
• Measurement of sputtering yields in atoms per ion.
• Molecular dynamics (MD) modeling to simulate ion-surface interactions.

Main Results:

• Sputtering yields for gold nanorods were enhanced by over an order of magnitude (100-1900 atoms/ion) compared to flat surfaces (≈50 atoms/ion).
• Proximity of collision cascades and thermal spikes to nanorod surfaces contribute to the yield enhancement.
• Molecular dynamics simulations indicated that a wider range of incident angles and the ejection of atomic clusters significantly increase sputtering yields.

Conclusions:

• Gold nanorods exhibit significantly enhanced sputtering yields under keV ion irradiation.
• Surface geometry and nanoscale effects play a critical role in ion-matter interactions.
• The findings provide insights into sputtering mechanisms at the nanoscale, relevant for advanced material fabrication.