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Silver-Polymer Composite Stars: Synthesis and Applications.

ABSTRACT: Colloidal "silver stars" were synthesized upon poly(lactic-co-glycolic) acid nanosphere templates via a facile two-step silver reduction method. Myriad dendrimer-like Ag star morphologies were synthesized by varying the amount of poly(vinyl alcohol) and trisodium citrate used during silver reduction. Scanning electron microscopy studies revealed that star-shaped silver-polymer composites possessing nanoscopic, fractal morphologies with diameters ranging from 500 nm to 7 ?m were produced. These composites have broad applications from antibacterial agents to catalysis; two such applications were tested here. Surface-enhanced Raman spectroscopy (SERS) studies showed multiple hot spots of SERS activity within a single star. Electrochemical catalysis experiments demonstrated the feasibility of using the silver stars instead of platinum for the oxygen reduction reaction in alkaline fuel cells.

SUBMITTER: Homan KA

PROVIDER: S-EPMC3109509 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Silver-Polymer Composite Stars: Synthesis and Applications.

Homan Kimberly A KA Chen Jeffrey J Schiano Adriane A Mohamed Mona M Willets Katherine A KA Murugesan Sankaran S Stevenson Keith J KJ Emelianov Stanislav S

Advanced functional materials 20110501 9

Colloidal "silver stars" were synthesized upon poly(lactic-co-glycolic) acid nanosphere templates via a facile two-step silver reduction method. Myriad dendrimer-like Ag star morphologies were synthesized by varying the amount of poly(vinyl alcohol) and trisodium citrate used during silver reduction. Scanning electron microscopy studies revealed that star-shaped silver-polymer composites possessing nanoscopic, fractal morphologies with diameters ranging from 500 nm to 7 μm were produced. These c ...[more]

PMID: 21660240

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