The multi-walled carbon nanotubes (MWCNTs) have
been widely applied as a promising raw material in
many areas of science and technology due to their
unique structure, mechanical, chemical, and electronic properties (Kim et al. 2006; Dai 2002). In recent
years, MWCNTs have been used to synthesize not
only various composite materials mainly including
polymer–MWCNT (Czerw et al. 2001), metal–
MWCNT (Liu et al. 2003), and TiO2–MWCNT
(Huang et al. 2009) composites, but also various
semiconductor–MWCNT (Woan et al. 2009) and
Quantum dot-SWCNT (Singh et al. 2009) hybrid
catalysts, where the CNTs can function as supporting
materials. The high surface area-to-volume ratios
obtained in the nanotube-supported semiconductor are
an additional advantage for using them in many
optoelectronic applications, such as photovoltaic cells
(Berson et al. 2007) and photocatalytic degradation
(Wang et al. 2008a, b). For photocatalytic degradation, catalytic properties of these solids are known to
be dependent upon the interaction between the
MWCNT and the semiconductor particles (Wu et al.
2008; Maurin et al. 2001). The introduction of
semiconductor particles into MWCNTs significantly