title: Diameter-dependent elastic modulus supports the metastable-catalyst growth of carbon nanotubes.
abstract: We measured the elastic modulus of individual multiwalled carbon nanotubes (MWCNTs) grown by catalytic chemical vapor deposition (CVD) over a broad diameter range (10-25 nm). Alternating current (ac) dielectrophoresis was used for efficient tube deposition, and atomic force microscope (AFM) force-displacement curve technique was used for stiffness measurements. The elastic modulus exhibits a strong diameter dependence, showing a difference of nearly 2 orders of magnitude in the 10-20 nm diameter range (thinner MWCNTs have higher elastic modulus). Our results support the metastable-catalyst model in which the catalyst's molten skin plays a key role.
authors.affiliation: Ecole Polytechnique Fédérale de Lausanne (EPFL), Institute of Physics of Complex Matter, 1015 Lausanne, Switzerland. lee.kyumin@gmail.com
authors.forename: Kyumin
authors.initials: K
authors.lastname: Lee
authors.forename: Branimir
authors.initials: B
authors.lastname: Lukić
authors.forename: Arnaud
authors.initials: A
authors.lastname: Magrez
authors.forename: Jin Won
authors.initials: JW
authors.lastname: Seo
authors.forename: G Andrew D
authors.initials: GA
authors.lastname: Briggs
authors.forename: Andrzej J
authors.initials: AJ
authors.lastname: Kulik
authors.forename: Laszló
authors.initials: L
authors.lastname: Forró
mesh_terms: D002384:Catalysis; D003198:Computer Simulation; D003460:Crystallization / Q000379:methods*; D004548:Elasticity; D004586:Electrophoresis / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008956:Models, Chemical; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D037742:Nanotubes, Carbon