Research of the processes of the internal and external
hydrogenization of the single-walled carbon nanotubes
I. Zaporotskova1 (
), N. Lebedev
1,
L. Chernozatonskii
2 (
)
1Volgograd State University, 400062, 2-ya Prodolnaya 30, Volgograd,
Russia.
2Institute of Biochemical Physics of RAS, 117334 Moscow, Russia.
One of the most interesting scientific directions of science today is the
study of nanotubes - new perspective materials. It is logical to assume use
tubulenes as the effective adsorbent of easy atoms, including hydrogen.
The items of information about the experimentally received tubulene
hy-drides recently were published. It is possible to assume three ways of
saturation of a nanotubes surface by atoms H: 1) atoms H adsorb on the
external surface of tubu-lene; 2) atoms H adsorb on the internal surface
(so-called capillary way of satura-tion); 3) the atoms H join both to the
external, and the internal surface simultane-ously.
The variant 1 already has received a theoretical substantiation. We
consid-ered variants 2 and 3. In result the following was received:
- The MNDO-accounts of the molecular cluster of nanotube such as (6,6) are
executed. The adsorbing atom H joined an internal surface of nanotube.
Opti-mum distance on which hydrogen adsorbs is established, and the energy of
adsorp-tion (2.3 eV) is found. Is found out, that adatom causes deformation of
a tubulene surface: carbon atom "is involved" inside of nanotube, and the
length of bond C-C are increased.
- The researches of various variants of the multiple adsorption of atoms H
on next 2-8 atoms C are carried out. They are executed have proved an
opportunity of unobstructed connection of adatoms to next atoms of carbon on
hexagon. The analysis of the energies of consecutive and simultaneous
adsorption has revealed power benefit of consecutive variant. It is revealed,
that each adatom H deforms a surface of nanotubes and as though prepares the
new active centre.
- The most probable variant of complete internal nanotube adsorption is
de-termined and optimum distance of connection of adatoms of hydrogen to atoms
of carbon of the internal surface is found.
- According to results of item 3 and results of earlier jobs were
investigated and the opportunity simultaneous complete internal and external
hydrogenization on the next atoms of carbon surface of nanotubes is
proved.
