esterification of nanotube-bound carboxylic acid
groups[3 4], which are associated with defects on as
prepared and acid treated nanotubes. Additionally, the
functionalization has also been utilized at the ends and/or
walls of CNTs noncovalently[5 6] to attach certain
functional groups onto nanotubes, improving
hydrophilicity and dispersion properties of nanotubes in
solvent.
SHIM et al[7] have reported that the adsorption of
surfactant Triton x-100 (C14H22O(C2H4O)n) on SWNTs is
effective in preventing nonspecific adsorption of
streptavidin on nanotubes via hydrophobic interactions
between the nanotubes and streptavidin (a kind of
protein). Since the adsorption of Triton can prevent
effectively the hydrophobic interactions between the
nanotubes and protein, it is believable that Triton can be
adsorbed onto CNTs as a wetting layer to enhance the
hydrophilic property of CNTs[8]. So, it is desirable that
nanotubes modified by Triton are the favorable parent
materials for fabricating nano-composites. For these
reasons, Triton x-100 was used to modify the surface of
ammonia-treated CNTs[9] for preparing nanoscale Ni-B
amorphous alloy catalyst supported on nanotubes. As a
new class of advanced materials for catalytic applications,
carbon nanotubes used as catalyst supports induce
peculiar activity and selectivity in catalytic reactions,
such as selective oxidation of H2S into elemental sulfur
and selective hydrogenation of nitrobenzene into
aniline[10]. In comparison with other Ni-based catalysts,
Ni-B amorphous alloy catalysts exhibit higher activity
and better selectivity, which have been widely studied by
researchers in the past two decades[11]. Therefore, it is
expected that the nanoscale Ni-B amorphous alloy
particles supported on nanotubes can be a potential

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