skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Tuning the conductance of carbon nanotubes with encapsulated molecules

Authors:
 [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Nanophase Materials Sciences; Center for Computational Sciences
Sponsoring Org.:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE Office of Science (SC)
OSTI Identifier:
966722
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nanotechnology; Journal Volume: 18; Journal Issue: 42
Country of Publication:
United States
Language:
English

Citation Formats

Meunier, Vincent, and Sumpter, Bobby G. Tuning the conductance of carbon nanotubes with encapsulated molecules. United States: N. p., 2007. Web. doi:10.1088/0957-4484/18/42/424032.
Meunier, Vincent, & Sumpter, Bobby G. Tuning the conductance of carbon nanotubes with encapsulated molecules. United States. doi:10.1088/0957-4484/18/42/424032.
Meunier, Vincent, and Sumpter, Bobby G. Mon . "Tuning the conductance of carbon nanotubes with encapsulated molecules". United States. doi:10.1088/0957-4484/18/42/424032.
@article{osti_966722,
title = {Tuning the conductance of carbon nanotubes with encapsulated molecules},
author = {Meunier, Vincent and Sumpter, Bobby G},
abstractNote = {},
doi = {10.1088/0957-4484/18/42/424032},
journal = {Nanotechnology},
number = 42,
volume = 18,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • In this work, graphite encapsulated Fe nanoparticles and thin carbon nanotubes (CNTs) supported on the pristine CNTs, respectively, were synthesized using plasma enhanced chemical vapor deposition via efficiently controlling the flow rate of discharging CH{sub 4} and H{sub 2} gas. The properties of the obtained hybrid materials were characterized with superconducting quantum interference and field emission measurements. The results showed that the encapsulated Fe nanoparticles had diameters ranging from 1 to 30 nm, and this hybrid nanocomposite exhibited a ferromagnetic behavior at room temperature. Thin CNTs with an average diameter of 6 nm were attached to the surface of themore » prepared CNTs, which exhibited a lower turn-on field and higher emission current density than the pristine CNTs. The Fe nanoparticles either encapsulated with graphite or used as catalyst for thin CNTs growth were all originated from the pyrolysis of ferrocene. - Graphical abstract: Graphite encapsulated Fe nanoparticles and thin carbon nanotubes supported on the pristine carbon nanotubes, respectively, were synthesized using plasma enhanced chemical vapor deposition.« less
  • We report experimental evidence of the formation by in situ electron-irradiation of single-walled carbon nanotubes (C NT) confined within boron nitride nanotubes (BN-NT). The electron radiation stemming from the microscope supplies the energy required by the amorphous carbonaceous structures to crystallize in a tubular form in a catalyst free procedure, at room temperature and high vacuum. The structural defects resulting from the interaction of the shapeless carbon with the BN nanotube are corrected in a self-healing process throughout the crystallinization. Structural changes developed during the irradiation process such as defects formation and evolution, shrinkage, and shortness of the BN-NT weremore » in situ monitored. The outer BN wall provides a protective and insulating shell against environmental Perturbations to the inner C-NT without affecting their electronic properties, as demonstrated by first principles calculations.« less
  • The structure stabilities and electronic properties are investigated by using ab initio self-consistent-field crystal orbital method based on density functional theory for the one-dimensional (1D) double-wall nanotubes made of n-gon SiO{sub 2} nanotubes encapsulated inside zigzag carbon nanotubes. It is found that formation of the combined systems is energetically favorable when the distance between the two constituents is around the Van der Waals scope. The obtained band structures show that all the combined systems are semiconductors with nonzero energy gaps. The frontier energy bands (the highest occupied band and the lowest unoccupied band) of double-wall nanotubes are mainly derived frommore » the corresponding carbon nanotubes. The mobilities of charge carriers are calculated to be within the range of 10{sup 2}–10{sup 4} cm{sup 2} V{sup −1} s{sup −1} for the hybrid double-wall nanotubes. Young’s moduli are also calculated for the combined systems. For the comparison, geometrical and electronic properties of n-gon SiO{sub 2} nanotubes are also calculated and discussed. - Graphical abstract: Structures and band structures of the optimum 1D Double walls nanotubes. The optimized structures are 3-gon SiO2@(15,0), 5-gon SiO2@(17,0), 6-gon SiO2@(18,0) and 7-gon SiO2@(19,0). - Highlights: • The structure and electronic properties of the 1D n-gon SiO{sub 2}@(m,0)s are studied using SCF-CO method. • The encapsulation of 1D n-gon SiO{sub 2} tubes inside zigzag carbon nanotubes can be energetically favorable. • The 1D n-gon SiO{sub 2}@(m,0)s are all semiconductors. • The mobility of charge carriers and Young’s moduli are calculated.« less
  • Nickel nanoparticles were prepared and uniformly supported on multi-walled carbon nanotubes (MWCNTs) by reduction route with CNTs as a reducing agent at 600 deg. C. As-prepared nickel nanoparticles were single crystalline with a face-center-cubic phase and a size distribution ranging from 10 to 50 nm, and they were characterized by transmission electron microscopy (TEM), high-resolution TEM and X-ray diffraction (XRD). These nickel nanoparticles would be coated with graphene layers, when they were exposed to acetylene at 600 deg. C. The coercivity values of nickel nanoparticles were superior to that of bulk nickel at room temperature.