commendable focus for wastewater treatment. To cite for evidence, palladium/
graphene oxide/BNC-based hybrid, robust, and reusable membrane was reported
to be effective enough in treating a contaminant cocktail of methylene blue,
4-nitrophenol, and rhodamine 6G, besides demonstrating a high efficiency for
methyl orange degradation during filtration (Fig. 4.4c) (Xu et al. 2018a, b). NCand NC-based composites have been explored across a wide spectrum of environmental applications, including toxicant-sensing, air purification, and mitigation of
toxic materials, including heavy metals and industrial dyes, water purification,
fabrication of antimicrobial membranes, catalysis, and energy storage, among others.
The applications of most of these materials rely on harnessing the specific pros,
emanating as a result of the interactions between diverse nanomaterials and
nanocellulose (Wei et al. 2014), as exemplified in a couple of studies cited
underneath.
Successful deployment of nanocellulosic sensors for detection and monitoring
of contaminants in the environment, food, cosmetics, and other stuffs has opened
new portals of research and commercial plausibility. The following examples stand
in testimony to this aspect. In recent years, albeit, silver nanoparticles (Ag NPs),
known for their antimicrobial attributes, have fetched their inclusion in a number of
consumer products, such as socks, deodorants etc., although their entry into the
environment and human body has been an issue of apprehension. In this regard, a
luminescent hydrogel with an orange/red emission at 617 nm was fabricated through
the incorporation of photosensitive bis(2,2-bipyridine)-[4-(4-methyl-2,2-bipyridin4-yl) proplylamine] ruthenium(II) dihexafluorophosphate complex in to negatively
charged carboxylated NC (Ruiz-Palomero et al. 2016). With a commendable sensitivity to the presence of AgNPs, the luminescent gels were established as apt sensors
for silver nanoparticles in real samples with recoveries in the range of 84–94%. The
pertinence of the study could be easily traced in the context of nanotoxicology, and
as such, designing nanocellulosic sensors for other nanomaterials (e.g., carbon
nanotubes, etc.) could be an interesting proposition. In a similar vein, a recent
study evinced the relevance of aerogels in concomitant monitoring and remediation
of environmental hazardous substances like organic dyes. Chook et al. (2015) had
exploited a porous aerogel based on AgNPs-functionalized cellulosic nanofibrils for
SERS (Raman spectroscopy-based) detection (at concentrations ranging from
5 Â 10
À3 M to 5 Â 10
À7 M) as well as catalytic degradation of rhodamine B.
Among the endeavors to develop a green air purification approach, the use of
films, foams, as well as sponges based on nanocellulose, exhibiting porous morphologies, seems quite attractive. In this regard, NC film-based technology for gas
separation has been reported. As a representative example, besides exhibiting
selective permeability for hydrogen gas, carboxylated NC membranes, post
subjecting to a soaking treatment with 0.1 M HCl, were found to display higher
H 2 permeation rates (Fukuzumi et al. 2013). By the same token, assessment of CO 2
capture (under 40% humidity) by aerogels (fabricated through freeze-drying of
dispersions of cellulosic nanofibrils and aminosilanes) registered a mark of
0.695 mmol CO 2 /g, while desorption was documented at 90
C under argon
ambiance (Gebald et al. 2011). The researchers had reported no negative trade-off
78
E. M. Abda and R. Konwarh
graphene oxide/BNC-based hybrid, robust, and reusable membrane was reported
to be effective enough in treating a contaminant cocktail of methylene blue,
4-nitrophenol, and rhodamine 6G, besides demonstrating a high efficiency for
methyl orange degradation during filtration (Fig. 4.4c) (Xu et al. 2018a, b). NCand NC-based composites have been explored across a wide spectrum of environmental applications, including toxicant-sensing, air purification, and mitigation of
toxic materials, including heavy metals and industrial dyes, water purification,
fabrication of antimicrobial membranes, catalysis, and energy storage, among others.
The applications of most of these materials rely on harnessing the specific pros,
emanating as a result of the interactions between diverse nanomaterials and
nanocellulose (Wei et al. 2014), as exemplified in a couple of studies cited
underneath.
Successful deployment of nanocellulosic sensors for detection and monitoring
of contaminants in the environment, food, cosmetics, and other stuffs has opened
new portals of research and commercial plausibility. The following examples stand
in testimony to this aspect. In recent years, albeit, silver nanoparticles (Ag NPs),
known for their antimicrobial attributes, have fetched their inclusion in a number of
consumer products, such as socks, deodorants etc., although their entry into the
environment and human body has been an issue of apprehension. In this regard, a
luminescent hydrogel with an orange/red emission at 617 nm was fabricated through
the incorporation of photosensitive bis(2,2-bipyridine)-[4-(4-methyl-2,2-bipyridin4-yl) proplylamine] ruthenium(II) dihexafluorophosphate complex in to negatively
charged carboxylated NC (Ruiz-Palomero et al. 2016). With a commendable sensitivity to the presence of AgNPs, the luminescent gels were established as apt sensors
for silver nanoparticles in real samples with recoveries in the range of 84–94%. The
pertinence of the study could be easily traced in the context of nanotoxicology, and
as such, designing nanocellulosic sensors for other nanomaterials (e.g., carbon
nanotubes, etc.) could be an interesting proposition. In a similar vein, a recent
study evinced the relevance of aerogels in concomitant monitoring and remediation
of environmental hazardous substances like organic dyes. Chook et al. (2015) had
exploited a porous aerogel based on AgNPs-functionalized cellulosic nanofibrils for
SERS (Raman spectroscopy-based) detection (at concentrations ranging from
5 Â 10
À3 M to 5 Â 10
À7 M) as well as catalytic degradation of rhodamine B.
Among the endeavors to develop a green air purification approach, the use of
films, foams, as well as sponges based on nanocellulose, exhibiting porous morphologies, seems quite attractive. In this regard, NC film-based technology for gas
separation has been reported. As a representative example, besides exhibiting
selective permeability for hydrogen gas, carboxylated NC membranes, post
subjecting to a soaking treatment with 0.1 M HCl, were found to display higher
H 2 permeation rates (Fukuzumi et al. 2013). By the same token, assessment of CO 2
capture (under 40% humidity) by aerogels (fabricated through freeze-drying of
dispersions of cellulosic nanofibrils and aminosilanes) registered a mark of
0.695 mmol CO 2 /g, while desorption was documented at 90
C under argon
ambiance (Gebald et al. 2011). The researchers had reported no negative trade-off
78
E. M. Abda and R. Konwarh