nanostructures highly efficient for photocatalytic water disinfection. For instance,
Wu et al. (2010) reported that TiO 2 nanobelts prepared by the hydrothermal method
and having {101} surface area show high photocatalytic oxidation activity for
bacteria cells due to the lower e
À /h
+ recombination compared to TiO 2 nanospheres.
Moreover, combining TiO 2 nanobelts with noble metal cocatalysts such as Au/TiO 2
nanobelts and Ag 2 O/TiO 2 nanobelts further enhanced the bacterial disinfection
process in water (Guo et al. 2015; Jin et al. 2013). In addition to this nanobelt,
materials based on β-AgVO 3 prepared by superficial hydrothermal method showed a
high photocatalytic activity under low-energy fluorescent light irradiation for the
disinfection of E. coli (Ren et al. 2010).
Nanotubes
In addition to the aforementioned one-dimensional nanostructure, nanotubes exhibit
hallow structure. This configuration enhances the electron transfer and reduces the
photogenerated charge recombination, making them an excellent choice for water
disinfection than bulk materials.
Wang et al. (2014) compared the photocatalytic activity of nanotube-based
graphitic C 3 N 4 with pure graphitic C 3 N 4 and P25-TiO 2 under visible light disinfection. This study showed that the nanotube-based graphitic C 3 N 4 material has better
disinfection performance than pure graphitic C 3 N 4 and P25-TiO 2 . This observed
activity was attributed to the high surface area and the active site of nanotube-based
graphitic C 3 N 4 photocatalytic material. Yang et al. (2016a, b) also reported that
TiO 2 -based nanotubes showed high photocatalytic activity for bacterial cell disinfection such as Actinobacillus actinomycetemcomitans and Staphylococcus aureus
under ultraviolet irradiation. Moreover, to increase the efficiency of nanotubes for
bacterial disinfection, Nie et al. (2014) prepared TiO 2 nanotubular photo-anode by
applying external photoelectrocatalysis for the disinfection of E. coli K-12 and its
mutant E. coli BW25113. The result shows that the photoelectrocatalysis TiO 2
nanotubular material has high efficiency in removing the bacterial cells and the
mutant reacted faster than with pure bulk photocatalytic TiO 2 nanotube. The
photocatalytic activity of nanotubular TiO 2 can be enhanced when applying an
external force leading to reduced recombination of the photogenerated charges.
However, both the photoelectrocatalysis and photocatalytic treatments showed moderate activities toward the mutant of E. coli BW25113 compared to the parental
bacteria E. coli K-12 cell. This difference was attributed to the genotype differences
(Wang et al. 2014).
In conclusion, one-dimensional nanostructure with different combinations of
nanobelts, nanorods, and nanowires has high performance in water disinfection
due to the superior-oriented charge transfer properties, large specific surface area,
and more active sites that attracted more attention in fabricated cost-efficient
photocatalysts material for water disinfection. However, there is a difference in the
characteristics and performance efficiency of photocatalytic material of nanobelts,
nanorods, and nanowires in their status of exposed facets, surface atomic
222
T. G. Ambaye et al.
Wu et al. (2010) reported that TiO 2 nanobelts prepared by the hydrothermal method
and having {101} surface area show high photocatalytic oxidation activity for
bacteria cells due to the lower e
À /h
+ recombination compared to TiO 2 nanospheres.
Moreover, combining TiO 2 nanobelts with noble metal cocatalysts such as Au/TiO 2
nanobelts and Ag 2 O/TiO 2 nanobelts further enhanced the bacterial disinfection
process in water (Guo et al. 2015; Jin et al. 2013). In addition to this nanobelt,
materials based on β-AgVO 3 prepared by superficial hydrothermal method showed a
high photocatalytic activity under low-energy fluorescent light irradiation for the
disinfection of E. coli (Ren et al. 2010).
Nanotubes
In addition to the aforementioned one-dimensional nanostructure, nanotubes exhibit
hallow structure. This configuration enhances the electron transfer and reduces the
photogenerated charge recombination, making them an excellent choice for water
disinfection than bulk materials.
Wang et al. (2014) compared the photocatalytic activity of nanotube-based
graphitic C 3 N 4 with pure graphitic C 3 N 4 and P25-TiO 2 under visible light disinfection. This study showed that the nanotube-based graphitic C 3 N 4 material has better
disinfection performance than pure graphitic C 3 N 4 and P25-TiO 2 . This observed
activity was attributed to the high surface area and the active site of nanotube-based
graphitic C 3 N 4 photocatalytic material. Yang et al. (2016a, b) also reported that
TiO 2 -based nanotubes showed high photocatalytic activity for bacterial cell disinfection such as Actinobacillus actinomycetemcomitans and Staphylococcus aureus
under ultraviolet irradiation. Moreover, to increase the efficiency of nanotubes for
bacterial disinfection, Nie et al. (2014) prepared TiO 2 nanotubular photo-anode by
applying external photoelectrocatalysis for the disinfection of E. coli K-12 and its
mutant E. coli BW25113. The result shows that the photoelectrocatalysis TiO 2
nanotubular material has high efficiency in removing the bacterial cells and the
mutant reacted faster than with pure bulk photocatalytic TiO 2 nanotube. The
photocatalytic activity of nanotubular TiO 2 can be enhanced when applying an
external force leading to reduced recombination of the photogenerated charges.
However, both the photoelectrocatalysis and photocatalytic treatments showed moderate activities toward the mutant of E. coli BW25113 compared to the parental
bacteria E. coli K-12 cell. This difference was attributed to the genotype differences
(Wang et al. 2014).
In conclusion, one-dimensional nanostructure with different combinations of
nanobelts, nanorods, and nanowires has high performance in water disinfection
due to the superior-oriented charge transfer properties, large specific surface area,
and more active sites that attracted more attention in fabricated cost-efficient
photocatalysts material for water disinfection. However, there is a difference in the
characteristics and performance efficiency of photocatalytic material of nanobelts,
nanorods, and nanowires in their status of exposed facets, surface atomic
222
T. G. Ambaye et al.