title: Engineering low-aspect ratio carbon nanostructures: nanocups, nanorings, and nanocontainers.
abstract: The synthesis of carbon nanostructures, with interesting morphologies, has created a revolution in nanotechnology; carbon nanotube is a case in point, but other nanoscale morphologies of graphitic carbon could provide compelling uses. In particular short structures, including very short nanotubes, have proven impossible to be grown by existing techniques due to the difficulty in controlling and terminating growth during initial stages. Here we present architectures engineered from graphitic carbon, having up to 10(5) times smaller length/diameter (L/D) ratios compared to conventional nanotubes, revealing unique morphologies of nanocups, nanorings, and large area connected nanocup arrays. Such highly engineered hollow nanostructures were fabricated using precisely controlled short nanopores inside anodic aluminum oxide templates. The nanocups were effectively used to hold and contain other nanomaterials, for example, metal nanoparticles, leading to the formation of multicomponent hybrid nanostructures with unusual morphologies. The results reported here open up possibilities to integrate new morphologies of graphitic carbon in nanotechnology applications.
authors.affiliation: Department of Mechanical & Industrial Engineering, Northeastern University, Boston, Massachusetts 02115, USA.
authors.forename: Hyunkyung
authors.initials: H
authors.lastname: Chun
authors.forename: Myung Gwan
authors.initials: MG
authors.lastname: Hahm
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Homma
authors.forename: Rebecca
authors.initials: R
authors.lastname: Meritz
authors.forename: Koji
authors.initials: K
authors.lastname: Kuramochi
authors.forename: Latika
authors.initials: L
authors.lastname: Menon
authors.forename: Lijie
authors.initials: L
authors.lastname: Ci
authors.forename: Pulickel M
authors.initials: PM
authors.lastname: Ajayan
authors.forename: Yung Joon
authors.initials: YJ
authors.lastname: Jung
mesh_terms: D002244:Carbon / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D002244:Carbon