Oxidation-Resistant Ag Nanostructures for Ultrastable Plasmonic Applications

Journal Article · Tue Jan 01 00:00:00 EST 2013 · Advanced Materials

DOI:https://doi.org/10.1002/adma.201204920· OSTI ID:1089267

Sachan, R ^[1]; Ramos, V ^[2]; Malasi, Abhinav ^[3]; Yadavali, S ^[2]; Bartley, B. ^[1]; Duscher, Gerd ^[2]; Kalyanaraman, Ramki ^[2]

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1. Materials Science and Engineering Department, University of Tennessee, Knoxville, TN, USA
2. University of Tennessee, Knoxville (UTK)
3. ORNL

Although Ag is considered a noble metal, its surface oxidizes relatively quickly on exposure to ambient air. On the nanos- cale, this degradation is especially deleterious to applications pertaining to its plasmonic behavior, such as surface plasmon resonance (SPR) sensing. In this Communication we show that oxidation of Ag nanoparticles under ambient conditions can be significantly suppressed by contacting Ag with immis- cible Co nanoparticles. As a consequence, while the plasmonic characteristic of pure Ag degrades by 25% within 500 h, Ag-Co nanoparticles take almost ten times longer to show a similar magnitude of decay in air, thus showing ultrastable plasmonics. We attribute this oxidation-resistance to a cathodic protection arising from galvanic coupling.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1089267
• Journal Information: Advanced Materials, Vol. 25, Issue 14; ISSN 0935-9648
• Country of Publication: United States
• Language: English