470
S. Saha et al.
Gange Programme” is one of the examples of that kind of attempt by the government
for the improvement of “Swachh Bharat Mission.”
For last few years, various strategies such as filtration, absorption, chlorination,
and UV irradiation have been employed to remove contaminants from wastewater.
Although some of the techniques are unsuccessful to completely disinfect harmful
contaminants such as organic dyes, harmful chemicals, and aquatic pathogenic
bacteria, viruses from wastewater as well as surface water and other techniques
are very costly (Anjum et al. 2016; Collivignarelli et al. 2018). Recently, it is
notified that several researchers are utilizing nanotechnology-based routes toward
the enhancement of wastewater remediation, whereas nanomaterials, specifically
graphene or reduced graphene oxide, carbon nanotube-based materials play very
crucial role as adsorbent, catalyst-supporting agent, bactericidal agents, and so on
(Yousefi et al. 2019; Saha et al. 2014; Han et al. 2019). More specifically, Graphene
is a two-dimensional single-layer nanosheet consisting of sp2-hybridized C-atoms
(Hass et al. 2008). Its unique planar nanostructure and wide-ranging extraordinary
properties offer various potential applications in a large number of areas such as water
purification, membrane preparation, sensor application, enhanced energy generation,
storage, and so on. On the other hand, metal and semiconductive metal nanoparticles
such as Zn, Ag, Ti, Fe, and their derivatives exhibited enhanced catalytic effect for
water disinfection (Han et al. 2019; Akhavan and Ghaderi 2009).
In terms of pathogen disinfection, Legionella, Salmonella typhimurium,
Escherichia coli (specific stain), Vibrio cholera, and Campylobacter jejuni are wellknown bacteria causing various harmful diseases and their complete inhibition from
water system is another major challenge in wastewater remediation, nowadays (Han
et al. 2019). It is also revealed that graphene and its composites are very effective
bactericidal agents and able to destroy bacterial cell walls as well as forming various
reactive species (H
+ , O
− , H 2 O 2 , OH.) in optimum condition. In this paper, we are
reviewing the role of graphene and reduced graphene oxide-laden composites for the
inhibition of pathogenic bacteria toward the enhancement of water purification.
2 Graphene as Antibacterial Agent
For the historical evolution of graphene-based materials, graphene oxide (GO) has
been experimentally analyzed for the last 40 years (Boehm et al. 1962, 1994). More
precisely, it is the oxidized form of graphite with various functional groups that
converted as reduced graphite oxide (RGO) or graphene after reduction by the strong
reducing agent like hydrazine hydrate. The basic structure of graphite and graphene
is demonstrated in Fig. 1.
It was first reported in the year of 2010 that physical structure and sharp edges
in graphene sheet are destroying cell walls in pathogen. Moreover, graphene sheets
were more capable to destroy the bacteria than general antibiotic and graphite oxide
also proficient to destroy the broad range of pathogens such as pathogenic bacteria,
protozoans, fungi, and so on. Due to the presence of various functional groups such
S. Saha et al.
Gange Programme” is one of the examples of that kind of attempt by the government
for the improvement of “Swachh Bharat Mission.”
For last few years, various strategies such as filtration, absorption, chlorination,
and UV irradiation have been employed to remove contaminants from wastewater.
Although some of the techniques are unsuccessful to completely disinfect harmful
contaminants such as organic dyes, harmful chemicals, and aquatic pathogenic
bacteria, viruses from wastewater as well as surface water and other techniques
are very costly (Anjum et al. 2016; Collivignarelli et al. 2018). Recently, it is
notified that several researchers are utilizing nanotechnology-based routes toward
the enhancement of wastewater remediation, whereas nanomaterials, specifically
graphene or reduced graphene oxide, carbon nanotube-based materials play very
crucial role as adsorbent, catalyst-supporting agent, bactericidal agents, and so on
(Yousefi et al. 2019; Saha et al. 2014; Han et al. 2019). More specifically, Graphene
is a two-dimensional single-layer nanosheet consisting of sp2-hybridized C-atoms
(Hass et al. 2008). Its unique planar nanostructure and wide-ranging extraordinary
properties offer various potential applications in a large number of areas such as water
purification, membrane preparation, sensor application, enhanced energy generation,
storage, and so on. On the other hand, metal and semiconductive metal nanoparticles
such as Zn, Ag, Ti, Fe, and their derivatives exhibited enhanced catalytic effect for
water disinfection (Han et al. 2019; Akhavan and Ghaderi 2009).
In terms of pathogen disinfection, Legionella, Salmonella typhimurium,
Escherichia coli (specific stain), Vibrio cholera, and Campylobacter jejuni are wellknown bacteria causing various harmful diseases and their complete inhibition from
water system is another major challenge in wastewater remediation, nowadays (Han
et al. 2019). It is also revealed that graphene and its composites are very effective
bactericidal agents and able to destroy bacterial cell walls as well as forming various
reactive species (H
+ , O
− , H 2 O 2 , OH.) in optimum condition. In this paper, we are
reviewing the role of graphene and reduced graphene oxide-laden composites for the
inhibition of pathogenic bacteria toward the enhancement of water purification.
2 Graphene as Antibacterial Agent
For the historical evolution of graphene-based materials, graphene oxide (GO) has
been experimentally analyzed for the last 40 years (Boehm et al. 1962, 1994). More
precisely, it is the oxidized form of graphite with various functional groups that
converted as reduced graphite oxide (RGO) or graphene after reduction by the strong
reducing agent like hydrazine hydrate. The basic structure of graphite and graphene
is demonstrated in Fig. 1.
It was first reported in the year of 2010 that physical structure and sharp edges
in graphene sheet are destroying cell walls in pathogen. Moreover, graphene sheets
were more capable to destroy the bacteria than general antibiotic and graphite oxide
also proficient to destroy the broad range of pathogens such as pathogenic bacteria,
protozoans, fungi, and so on. Due to the presence of various functional groups such