nanostructured surfaces is an important challenge. The following are the basic
innate factors which influence the function as adsorbent of nanoparticles in
solution or substrate: location of the most atoms in the surface, high surface
area, high chemical activity, high adsorptive capacity, lack of internal diffusional resistance, and high surface binding energy. Each of the above properties
successively leads to the significant fraction of atoms or molecules associated
with surfaces and interfaces and increases the potential impact of surface
accessibility and affinity, surface enrichment, number of active sorption sites,
and, accordingly, surface energy toward specific analytes. Because of capillary
and sorption effects, the high surface area present in nanomaterials may retain
solvents in circumstances that can surprise researchers. Even using surface tools,
it can sometimes be difficult to characterize the nature of the actual
nanomaterials surfaces.
(b) External Functionalization: Using the various functional groups, a number of
changes emerge in the surface properties of nanomaterials. Coupling the wide
variety of nanomaterials with different external functionalization methods will
result in excellent adsorption properties. Further functionalization of the surface
prevents NMs from aggregating and provides their selectivity. Intended coatings
may have a significant impact on a variety of nanoparticle properties.
Functionalized groups induce important characteristics to the adsorbents such
as high absorption capacity (often measured as the breakthrough volume for a
flowing system) and rapid desorption. The quest for functionalized groups is an
important factor to improve analytical parameters such as selectivity, affinity,
stability, and adsorption capacity. This is done by introducing various organic
donor atoms to the nanomaterials’ surface and improving the interactions with
the analytes of interest, such as hydrophilicity or polarity. Amino and oxygen
groups are known to be able to coordinate to transition metals via electrostatic
interactions.
4.4
Nanoparticles in Water Treatment
Nanoparticles have two key properties that make them particularly attractive as
sorbents. First, on a mass basis, they have much larger surface areas than bulk
particles. Second, they can also be functionalized with various chemical groups to
increase their affinity toward target compounds. Applications of nanoparticles as
adsorbents for high efficient removal of pollutants from wastewater must satisfy the
following criterions:
1. The nanoparticles act as nanosorbents are nontoxic.
2. These nanosorbents must show relatively high sorption capacities and selectivity
even to the low concentration of pollutants.
3. The adsorbed pollutant could be removed from the surface of the nanoadsorbent
very easily.
76
A. Kaur
innate factors which influence the function as adsorbent of nanoparticles in
solution or substrate: location of the most atoms in the surface, high surface
area, high chemical activity, high adsorptive capacity, lack of internal diffusional resistance, and high surface binding energy. Each of the above properties
successively leads to the significant fraction of atoms or molecules associated
with surfaces and interfaces and increases the potential impact of surface
accessibility and affinity, surface enrichment, number of active sorption sites,
and, accordingly, surface energy toward specific analytes. Because of capillary
and sorption effects, the high surface area present in nanomaterials may retain
solvents in circumstances that can surprise researchers. Even using surface tools,
it can sometimes be difficult to characterize the nature of the actual
nanomaterials surfaces.
(b) External Functionalization: Using the various functional groups, a number of
changes emerge in the surface properties of nanomaterials. Coupling the wide
variety of nanomaterials with different external functionalization methods will
result in excellent adsorption properties. Further functionalization of the surface
prevents NMs from aggregating and provides their selectivity. Intended coatings
may have a significant impact on a variety of nanoparticle properties.
Functionalized groups induce important characteristics to the adsorbents such
as high absorption capacity (often measured as the breakthrough volume for a
flowing system) and rapid desorption. The quest for functionalized groups is an
important factor to improve analytical parameters such as selectivity, affinity,
stability, and adsorption capacity. This is done by introducing various organic
donor atoms to the nanomaterials’ surface and improving the interactions with
the analytes of interest, such as hydrophilicity or polarity. Amino and oxygen
groups are known to be able to coordinate to transition metals via electrostatic
interactions.
4.4
Nanoparticles in Water Treatment
Nanoparticles have two key properties that make them particularly attractive as
sorbents. First, on a mass basis, they have much larger surface areas than bulk
particles. Second, they can also be functionalized with various chemical groups to
increase their affinity toward target compounds. Applications of nanoparticles as
adsorbents for high efficient removal of pollutants from wastewater must satisfy the
following criterions:
1. The nanoparticles act as nanosorbents are nontoxic.
2. These nanosorbents must show relatively high sorption capacities and selectivity
even to the low concentration of pollutants.
3. The adsorbed pollutant could be removed from the surface of the nanoadsorbent
very easily.
76
A. Kaur