We demonstrate that multiwalled BxCyNz nanotubes can be efficiently converted to BN multiwalled nanotubes via an oxidation treatment. The microstructure and composition of the precursors and final products have been characterized by high-resolution transmission electron microscopy, electron energy-loss spectroscopy, and energy dispersive x-ray spectroscopy. The conversion process is monitored by thermogravimetric analysis. Carbon layers of BxCyNz nanotubes start to oxidize at 550 °C, thereby transforming BxCyNz nanotubes into pure BN nanotubes. The remarkable thermal stability of pure BN nanotubes in an oxidizing environment is also established.

1.
N. G.
Chopra
,
R. J.
Luyken
,
K.
Cherrey
,
V. H.
Crespi
,
M. L
Cohen
,
S. G.
Louie
, and
A.
Zettl
,
Science
269
,
966
(
1995
).
Google Scholar
 
2.
Z.
Weng-Sieh
,
K.
Cherrey
,
N. G.
Chopra
,
X.
Blasé
,
Y.
Miyamoto
,
A.
Rubio
,
M. L.
Cohen
,
S. G.
Louie
,
A.
Zettl
, and
R.
Gronsky
,
Phys. Rev. B
51
,
11229
(
1995
).
Google Scholar
 
3.
X.
Blase
,
J.-Ch.
Charlier
,
A. De
Vita
, and
R.
Car
,
Appl. Phys. A: Mater. Sci. Process.
A68
,
293
(
1999
).
Google Scholar
 
4.
W.
Han
,
Y.
Bando
,
K.
Kurashima
, and
T.
Sato
,
Appl. Phys. Lett.
73
,
3085
(
1998
).
Google Scholar
 
5.
W.
Han
,
Y.
Bando
,
K.
Kurashima
, and
T.
Sato
,
Jpn. J. Appl. Phys., Part 2
38
,
L755
(
1999
).
Google Scholar
 
6.
W.
Han
,
L.
Bourgeois
,
Y.
Bando
,
K.
Kurashima
, and
T.
Sato
,
Appl. Phys. A: Mater. Sci. Process.
A71
,
83
(
2000
).
Google Scholar
 
7.
D.
Golberg
,
Y.
Bando
,
K.
Kurashima
, and
T.
Sato
,
Chem. Phys. Lett.
323
,
185
(
2000
).
Google Scholar
 
8.
S. C.
Tsang
,
P. J. F.
Harris
, and
M. L. H.
Green
,
Nature (London)
362
,
520
(
1993
).
Google Scholar
 
9.
T. W.
Ebbesen
,
P. M.
Ajayan
,
H.
Hiura
, and
K.
Tanigaki
,
Nature (London)
367
,
519
(
1994
).
Google Scholar
 
10.
As a comparation, we also measure the amorphous porous carbon and graphite particles by TGA. The masses of amorphous porous carbon graphite particles start to decrease at about 400 and 600 °C, respectively.
11.
W.
Han
,
J.
Cumings
,
X.
Hunag
,
K.
Bradley
, and
A.
Zettl
,
Chem. Phys. Lett.
346
,
368
(
2001
).
Google Scholar
 
12.
There are about 50% nanotubes in the sample. Others are BxCyNz and BN particles, wires and Fullerene-like nano particles. There are not pure carbon materials in the sample. For BxCyNz nanotubes, there are no amorphous carbon coating. The mass loss data by TGA is from all the stuffs of the sample (14%). The mass loss data (9%) by EELS is only from nanotubes. The mass loss data difference comes from two reasons: (1) the measurement error (e.g., due to uncertainties in background subtraction of EELS data, the calculated B/C ratio has an estimated error of 20%); (2) the non-nanotubes BxCyNz materials might have more carbon content than that of nanotubes.
13.
K.
Suenaga
,
C.
Colliex
,
N.
Demoncy
,
A.
Loiseau
,
H.
Pascard
, and
F.
Willaime
,
Science
278
,
653
(
1997
).
Google Scholar
 
This content is only available via PDF.
© 2002 American Institute of Physics.
2002
American Institute of Physics
You do not currently have access to this content.