title: Crystal overgrowth on gold nanorods: tuning the shape, facet, aspect ratio, and composition of the nanorods.
abstract: Electrochemically prepared Au nanorods were used as seeds for the overgrowth of thin shells of gold, silver, and palladium by using a mild reducing agent, ascorbic acid, in the presence of surfactants at ambient condition. The unique crystal facets of the starting nanorods results in anisotropic crystal overgrowth. The overgrowth rates along different crystallographical directions can be further regulated by adding foreign ions or by using different metal reduction methods. This overgrowth study provides insights on how different metal ions could be reduced preferentially on different Au nanorod surfaces, so that the composition, aspect ratio, shape, and facet of the resulting nanostructures can be rationally tuned. These surfactant-stabilized bimetallic Au(core)M(shell) (M=Au, Ag, Pd) nanorod colloids might serve as better substrates in surface-enhanced Raman spectroscopy as well as exhibiting enhanced catalytic properties.
authors.affiliation: Department of Chemistry, University of California, Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
authors.forename: Jae Hee
authors.initials: JH
authors.lastname: Song
authors.forename: Franklin
authors.initials: F
authors.lastname: Kim
authors.forename: Daniel
authors.initials: D
authors.lastname: Kim
authors.forename: Peidong
authors.initials: P
authors.lastname: Yang
mesh_terms: D003460:Crystallization; D004563:Electrochemistry; D006046:Gold / Q000737:chemistry*; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry; D010316:Particle Size; D012680:Sensitivity and Specificity; D012834:Silver / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013499:Surface Properties
chemical_list: D012834:Silver; D010165:Palladium; D006046:Gold