ID | 114004 |
Author |
Setoura, Kenji
Osaka University
Strasser, Michael
University of Tokushima
Uwada, Takayuki
Josai University
Miyasaka, Hiroshi
Osaka University
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Content Type |
Journal Article
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Description | Pump-probe transient extinction spectroscopy was applied to analyze 355-nm picosecond laser heating-induced phenomena of 60-nm-diameter aqueous gold nanoparticles (AuNPs) under a high pressure of 60 MPa. Kinetic spectroscopy revealed that a supercritical layer surrounding the AuNP nucleated with a lifetime of approximately 1 ns in its dynamic expansion and decay behavior for a fluence of 19.6 mJ cm−2. Moreover, we observed in the post-mortem transmission electron micrographs a number of fragments, a small percentage of size-reduced cores, and erupted particles, among the intact particles after 60 shots, suggesting that evaporation occurs under laser illumination. The particle temperature calculation indicated that evaporation begins with a liquid droplet AuNP surrounded by a supercritical layer at temperatures below the boiling point of gold. By applying high pressure, we are able to obtain a clear picture of the evaporation event, which was not possible at ambient pressure because the forming bubble caused particle temperatures to rise uncontrollably. In this study, we shed light on the critical role of the supercritical layer formed around the AuNP under high pressure during laser-induced evaporation.
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Description Alternative | Pulsed-laser illumination of aqueous gold colloids under high pressure enables the evaporation from liquid droplets surrounded by supercritical water layer.
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Journal Title |
Physical Chemistry Chemical Physics
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ISSN | 14639076
14639084
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NCID | AA11301773
AA11723355
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Publisher | The Royal Society of Chemistry
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Volume | 18
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Issue | 6
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Start Page | 4994
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End Page | 5004
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Published Date | 2016-01-14
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EDB ID | |
DOI (Published Version) | |
URL ( Publisher's Version ) | |
FullText File | |
language |
eng
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TextVersion |
Author
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departments |
Science and Technology
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