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Collision-spike Sputtering of Au Nanoparticles.

Sandoval L, Urbassek HM - Nanoscale Res Lett (2015)

Bottom Line: While this feature is reasonably well understood for collision-cascade sputtering, we explore it in the regime of collision-spike sputtering using molecular-dynamics simulation.For the particular case of 200-keV Xe bombardment of Au particles, we show that collision spikes lead to abundant sputtering with an average yield of 397 ± 121 atoms compared to only 116 ± 48 atoms for a bulk Au target.The sputter yield of supported nanoparticles is estimated to be around 80 % of that of free nanoparticles due to the suppression of forward sputtering.

View Article: PubMed Central - PubMed

Affiliation: Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA.

ABSTRACT
Ion irradiation of nanoparticles leads to enhanced sputter yields if the nanoparticle size is of the order of the ion penetration depth. While this feature is reasonably well understood for collision-cascade sputtering, we explore it in the regime of collision-spike sputtering using molecular-dynamics simulation. For the particular case of 200-keV Xe bombardment of Au particles, we show that collision spikes lead to abundant sputtering with an average yield of 397 Β± 121 atoms compared to only 116 Β± 48 atoms for a bulk Au target. Only around 31 % of the impact energy remains in the nanoparticles after impact; the remainder is transported away by the transmitted projectile and the ejecta. The sputter yield of supported nanoparticles is estimated to be around 80 % of that of free nanoparticles due to the suppression of forward sputtering.

No MeSH data available.


Related in: MedlinePlus

Angular distribution of sputtered particles. a Data obtained as average over central impacts. b Average over all impacts
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Fig7: Angular distribution of sputtered particles. a Data obtained as average over central impacts. b Average over all impacts

Mentions: Figure 7a presents the angular distribution of sputtered particles for central impacts and Fig. 7b averages over all impacts. The angular distribution, f(πœ—), is defined such that f(πœ—) sinπœ—dπœ— equals the number of atoms emitted in the angular range (πœ—,πœ—+dπœ—). Thus, isotropic emission from the NP, f(πœ—)=const, corresponds to a sine distribution in Fig. 7. Both the average over central impacts, Fig. 7a, and the average over all impacts, Fig. 7b, show a more backward-oriented emission. The forward-sputter fraction is 19 % when averaged over all events.Fig. 7


Collision-spike Sputtering of Au Nanoparticles.

Sandoval L, Urbassek HM - Nanoscale Res Lett (2015)

Angular distribution of sputtered particles. a Data obtained as average over central impacts. b Average over all impacts
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4526510&req=5

Fig7: Angular distribution of sputtered particles. a Data obtained as average over central impacts. b Average over all impacts
Mentions: Figure 7a presents the angular distribution of sputtered particles for central impacts and Fig. 7b averages over all impacts. The angular distribution, f(πœ—), is defined such that f(πœ—) sinπœ—dπœ— equals the number of atoms emitted in the angular range (πœ—,πœ—+dπœ—). Thus, isotropic emission from the NP, f(πœ—)=const, corresponds to a sine distribution in Fig. 7. Both the average over central impacts, Fig. 7a, and the average over all impacts, Fig. 7b, show a more backward-oriented emission. The forward-sputter fraction is 19 % when averaged over all events.Fig. 7

Bottom Line: While this feature is reasonably well understood for collision-cascade sputtering, we explore it in the regime of collision-spike sputtering using molecular-dynamics simulation.For the particular case of 200-keV Xe bombardment of Au particles, we show that collision spikes lead to abundant sputtering with an average yield of 397 ± 121 atoms compared to only 116 ± 48 atoms for a bulk Au target.The sputter yield of supported nanoparticles is estimated to be around 80 % of that of free nanoparticles due to the suppression of forward sputtering.

View Article: PubMed Central - PubMed

Affiliation: Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA.

ABSTRACT
Ion irradiation of nanoparticles leads to enhanced sputter yields if the nanoparticle size is of the order of the ion penetration depth. While this feature is reasonably well understood for collision-cascade sputtering, we explore it in the regime of collision-spike sputtering using molecular-dynamics simulation. For the particular case of 200-keV Xe bombardment of Au particles, we show that collision spikes lead to abundant sputtering with an average yield of 397 Β± 121 atoms compared to only 116 Β± 48 atoms for a bulk Au target. Only around 31 % of the impact energy remains in the nanoparticles after impact; the remainder is transported away by the transmitted projectile and the ejecta. The sputter yield of supported nanoparticles is estimated to be around 80 % of that of free nanoparticles due to the suppression of forward sputtering.

No MeSH data available.


Related in: MedlinePlus