PHYS 482 |
| Unique hollow gold-silver double shell nanospheres (AuAgHNSs) were synthesized and characterized to explore their structural properties, optical absorption, and surface enhanced Raman scattering (SERS) at the single particle level. Transmission electron microscopy (TEM) revealed the uniform silver outer shell of approximately 3 nm deposited by seed mediated growth on 28 nm hollow gold nanospheres (HGNs). AuAgHNSs possess a plasmon band that combines those of both the silver and gold shells to expand the absorption profile in the UV-visible range. The AuAgHNSs showed a 4-5X enhancement of SERS over the HGNs with mercaptobenzoic acid (MBA) as the probe molecule. Consistency measurements indicated that AuAgHNSs generated the most consistent SERS over other silver nanostructures studied. Incidentally, a change in peak ratios of the two MBA ring breathing modes was observed between the HGNs and AuAgHNSs. This is attributed to the difference in binding between the sulfur to gold and silver surfaces. |
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PHYS Poster Session - Nanostructured Materials and Nanophotonics
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster
Sci-Mix
Division of Physical Chemistry |