title: Processes controlling the diameter distribution of single-walled carbon nanotubes during catalytic chemical vapor deposition.
abstract: Single-walled carbon nanotubes are grown by catalytic chemical vapor deposition in various conditions of temperature and carbon precursor pressure. Systematic analyses of the Raman radial breathing modes at two laser wavelengths are used to monitor the evolution of the diameter distribution. Two distinct domains with opposite influences of the temperature and the precursor pressure on the diameter distribution are evidenced. Thanks to specially designed experiments made of two successive growths, three processes are identified to influence the diameter distribution during the nanotube growth: (i) at too low precursor pressure, nanotube nucleation cannot occur on the smallest catalyst particles; (ii) at low temperature and high precursor pressure, small catalyst particles are preferably encapsulated by disordered carbon structures; (iii) at high temperature, catalyst coarsening causes the disappearance of the smallest catalyst particles.
authors.affiliation: Laboratoire des Colloïdes, Verres et Nanomatériaux, UMR 5587 CNRS-UM2, University Montpellier 2 , Place Bataillon, 34095 Montpellier Cedex 5, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Picher
authors.forename: Eric
authors.initials: E
authors.lastname: Anglaret
authors.forename: Raul
authors.initials: R
authors.lastname: Arenal
authors.forename: Vincent
authors.initials: V
authors.lastname: Jourdain
mesh_terms: D002384:Catalysis; D003460:Crystallization / Q000379:methods*; D005740:Gases / Q000737:chemistry; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D005740:Gases; D046911:Macromolecular Substances; D037742:Nanotubes, Carbon