arrangement, and oxygen vacancies, so more research must be carried out in the
future in optimizing the main parameters to produce one-dimensional nanostructure
with different combinations of nanobelts, nanorods, and nanowires to increase
photocatalytic activity for water disinfection process.
7.2.3 Two-Dimensional Nanostructured Materials
Currently, two-dimensional photocatalytic materials in the water disinfection process get more attention because they have a specific surface area and specific
thickness. At the same time, it balances the drawback of the photocatalytic process
compared with zero-dimensional, one-dimensional, and bulk photocatalytic material
due to having these properties. In the last decade, more research are carried out to
use two-dimensional novel nanomaterial such as graphene, metal oxides such as
TiO 2 and WO 3 nanosheets, graphitic carbon nitride, transition metal
dichalcogenides, metal oxyhalides (e.g., BiOB rand BiOI), and metallates (e.g.,
Bi 2 WO 4 and Bi 2 MoO 6 ) as novel photocatalyst material in water disinfection process
has been published (Carlson et al. 2016; Liu et al. 2014; Miao et al. 2016; Pan et al.
2008; Sajan et al. 2016; Shi et al. 2014; Wang et al. 2012; Yang et al. 2016b; Zhang
et al. 2016b, 2016c), though most of the research on water disinfection investigated
metal oxyhalides, graphite carbon nitride, and graphene nanosheets of
two-dimensional nanomaterials as photocatalytic material. For this reason some
research shows that uisng metal oxyhalides such as BiOBr nanosheets as
photocatalyst showed promising result in removing organic contaminants under
visible light (Ye et al. 2014; Zhang et al. 2014).
According to Wu et al. (2015), in their resaerch to disinfect microorganism such
as E. coli using BiOBr nanosheets as a photocatalytic material produced by hydrothermal condition having a specific surface of {001} and {010} nanosheets as a
shows that the nanosheets with surface {001} can remove the bacteria cells to
about 10
7 CFU mL
À1 under visible light within 2 h. In contrast, the nanosheets
with{010} surface take about 6 h for the same removal efficiency. This can be due to
the arrangement of nanosheets with surface {001} perpendicular to the direction of
the electric field. Moreover, they claimed that the removal of bacterial cells was
depended upon the surface of nanosheets and their atomic arrangement.
This opens an avenue for the production of self-doped and exogenously doped
nanosheets of BiOBr with a high percentage of {001} facets as photocatalytic
material for the disinfection process under visible light (Wu et al. 2016a, b, 2017).
For example, Wu et al. (2016a, b) fabricated nanosheets with {001} facets for
removal of bacteria using self-doped B-BiOBr before treatment shows that total
removal of the bacteria happened within 30 min under visible light. This approach
involves the enhancement of light absorption, charge separation, and total removal
of bacteria with the use of B-BiOBr as photocatalyst material, followed by hydrothermal treatment allowing the oxidation of BiOBr to Bi
5+ for complete removal of
bacteria in disinfection process in UV irradiation (An et al. 1996). However,
posttreated B-BiOBr with NaOH under Xenon lamp has led to the oxidation of the
7 Photocatalytic Nanomaterials for Bacterial Disinfection
223
future in optimizing the main parameters to produce one-dimensional nanostructure
with different combinations of nanobelts, nanorods, and nanowires to increase
photocatalytic activity for water disinfection process.
7.2.3 Two-Dimensional Nanostructured Materials
Currently, two-dimensional photocatalytic materials in the water disinfection process get more attention because they have a specific surface area and specific
thickness. At the same time, it balances the drawback of the photocatalytic process
compared with zero-dimensional, one-dimensional, and bulk photocatalytic material
due to having these properties. In the last decade, more research are carried out to
use two-dimensional novel nanomaterial such as graphene, metal oxides such as
TiO 2 and WO 3 nanosheets, graphitic carbon nitride, transition metal
dichalcogenides, metal oxyhalides (e.g., BiOB rand BiOI), and metallates (e.g.,
Bi 2 WO 4 and Bi 2 MoO 6 ) as novel photocatalyst material in water disinfection process
has been published (Carlson et al. 2016; Liu et al. 2014; Miao et al. 2016; Pan et al.
2008; Sajan et al. 2016; Shi et al. 2014; Wang et al. 2012; Yang et al. 2016b; Zhang
et al. 2016b, 2016c), though most of the research on water disinfection investigated
metal oxyhalides, graphite carbon nitride, and graphene nanosheets of
two-dimensional nanomaterials as photocatalytic material. For this reason some
research shows that uisng metal oxyhalides such as BiOBr nanosheets as
photocatalyst showed promising result in removing organic contaminants under
visible light (Ye et al. 2014; Zhang et al. 2014).
According to Wu et al. (2015), in their resaerch to disinfect microorganism such
as E. coli using BiOBr nanosheets as a photocatalytic material produced by hydrothermal condition having a specific surface of {001} and {010} nanosheets as a
shows that the nanosheets with surface {001} can remove the bacteria cells to
about 10
7 CFU mL
À1 under visible light within 2 h. In contrast, the nanosheets
with{010} surface take about 6 h for the same removal efficiency. This can be due to
the arrangement of nanosheets with surface {001} perpendicular to the direction of
the electric field. Moreover, they claimed that the removal of bacterial cells was
depended upon the surface of nanosheets and their atomic arrangement.
This opens an avenue for the production of self-doped and exogenously doped
nanosheets of BiOBr with a high percentage of {001} facets as photocatalytic
material for the disinfection process under visible light (Wu et al. 2016a, b, 2017).
For example, Wu et al. (2016a, b) fabricated nanosheets with {001} facets for
removal of bacteria using self-doped B-BiOBr before treatment shows that total
removal of the bacteria happened within 30 min under visible light. This approach
involves the enhancement of light absorption, charge separation, and total removal
of bacteria with the use of B-BiOBr as photocatalyst material, followed by hydrothermal treatment allowing the oxidation of BiOBr to Bi
5+ for complete removal of
bacteria in disinfection process in UV irradiation (An et al. 1996). However,
posttreated B-BiOBr with NaOH under Xenon lamp has led to the oxidation of the
7 Photocatalytic Nanomaterials for Bacterial Disinfection
223