title: Centrifugal shape sorting and optical response of polyhedral gold nanoparticles.
abstract: A centrifugal route for separating small {110}-faceted gold nanostructures, namely rhombic dodecahedra (RD) and triangular bipyramids (BPs), which form simultaneously during synthesis and cannot be separated by means of conventional filtration methods, is presented. The centrifuged solution shows two distinct bands: i) RD and ii) BPs, as verified in the corresponding scanning electron microscopy images. The sorted BPs show a refractive index dependence 2.5 times that of the as-synthesized, unsorted mixture.
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA.
authors.forename: Yu Jin
authors.initials: YJ
authors.lastname: Shin
authors.forename: Emilie
authors.initials: E
authors.lastname: Ringe
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Personick
authors.forename: M Fernanda
authors.initials: MF
authors.lastname: Cardinal
authors.forename: Chad A
authors.initials: CA
authors.lastname: Mirkin
authors.forename: Laurence D
authors.initials: LD
authors.lastname: Marks
authors.forename: Richard P
authors.initials: RP
authors.lastname: Van Duyne
authors.forename: Mark C
authors.initials: MC
authors.lastname: Hersam
mesh_terms: D002498:Centrifugation / Q000379:methods*; D006046:Gold / Q000737:chemistry* / Q000302:isolation & purification*; D008027:Light; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012031:Refractometry; D012542:Scattering, Radiation; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D006046:Gold
keywords: bipyramids; density gradient centrifugation; gold nanoparticles; localized surface plasmon resonance; refractive index sensing; rhombic dodecahedra