On the origin of preferential growth of semiconducting single-walled carbon nanotubes.
A correlation is observed between the diameters (d) of single-walled carbon nanotubes and the percentages of metallic and semiconducting tubes synthesized at 600 degrees C by plasma-assisted chemical vapor deposition. Small tubes (d approximately 1.1 nm) show semiconductor percentages that are much higher than expected for a random chirality distribution. Density functional theory calculations reveal differences in the heat of formation energies for similar-diameter metallic, quasi-metallic, and semiconducting nanotubes. Semiconducting tubes exhibit the lowest energies and the stabilization scales with approximately 1/d(2). This could be a thermodynamic factor in the preferential growth of small semiconducting nanotubes.
Li
Yiming
Y
Department of Chemistry and Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA.
Peng
Shu
S
Mann
David
D
Cao
Jien
J
Tu
Ryan
R
Cho
K J
KJ
Dai
Hongjie
H