(b) 1D nanomaterials: At the nanometer scale, NMs having one dimension includes
nanotubes, nanowires, fibers, fibrils, and dendrimers.
(c) 2D nanomaterials: These are materials that are measured outside the nanoscale.
Two-dimensional NMs are generally surface coatings or thin films. Surface
coatings have potential applications in electronics, optics, and magneto-optic
devices, fiber-optic systems, information storage systems, biological and chemical sensors. At an atomic level (monolayer), thin films can be controlled
(Seshan 2002).
(d) 3D nanomaterials: In all three dimensions materials at the nanoscale are known
as 3D NMs that constitute nanocrystals, fullerenes, quantum dots, colloids, and
precipitates. Some common types of NMs are nanofibers, nanotubes, quantum
dots, dendrimers, and fullerenes.
2.3.2 Morphology and Nanocomposites
(a) Morphology: Different NPs have different morphology and it occurs according
to high and low aspect ratio particles. High aspect ratio NPs are nanowires and
nanotubes whereas NPs with low aspect ratio include spherical, cubic, oval,
helical, prism and pillar shapes.
(b) Nanocomposites: Significant progress has been made in recent years associated
with nanocomposites with the increasing development of new technologies in
fields like ferrofluids, magnetic nanospheres, and microspheres. Microspheres
and nanospheres comprising of a magnetic core surrounded by non-magnetic
matrix are utilized in various biological applications (Krishnan 2010). These
types of nanocomposites are used as a carrier by utilizing the magnetic field.
Nanocomposites having biocompatible coatings help in preventing the aggregation and protects the body from toxicity also.
According to few reports, it was documented that for in vitro applications, biocompatible coatings are not necessary, and particles can be coated with nontoxic
materials.
Supermagnetic types of composites are made by surrounding the supermagnetic
nanocrystals in a non-magnetic matrix, for example, nanoporous silica or polystyrene (Leun and SenGupta 2000; Jain et al. 2008; Behrens 2011). Under the external
magnetic field, formed colloidal particles maintain the superparamagnetic behavior
and display higher magnetization.
NMs chemical composition constitutes of one or several materials. Naturally
formed NPs are often formed of materials agglomerations with different types of
compositions, whereas pure NMs having a single composition can be synthesized
in vitro using various methods.
There are basically different chemical orderings by which elemental atoms are
arranged within the NMs (Borbón 2011; Tiruvalam et al. 2011).
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V. Dogra et al.
nanotubes, nanowires, fibers, fibrils, and dendrimers.
(c) 2D nanomaterials: These are materials that are measured outside the nanoscale.
Two-dimensional NMs are generally surface coatings or thin films. Surface
coatings have potential applications in electronics, optics, and magneto-optic
devices, fiber-optic systems, information storage systems, biological and chemical sensors. At an atomic level (monolayer), thin films can be controlled
(Seshan 2002).
(d) 3D nanomaterials: In all three dimensions materials at the nanoscale are known
as 3D NMs that constitute nanocrystals, fullerenes, quantum dots, colloids, and
precipitates. Some common types of NMs are nanofibers, nanotubes, quantum
dots, dendrimers, and fullerenes.
2.3.2 Morphology and Nanocomposites
(a) Morphology: Different NPs have different morphology and it occurs according
to high and low aspect ratio particles. High aspect ratio NPs are nanowires and
nanotubes whereas NPs with low aspect ratio include spherical, cubic, oval,
helical, prism and pillar shapes.
(b) Nanocomposites: Significant progress has been made in recent years associated
with nanocomposites with the increasing development of new technologies in
fields like ferrofluids, magnetic nanospheres, and microspheres. Microspheres
and nanospheres comprising of a magnetic core surrounded by non-magnetic
matrix are utilized in various biological applications (Krishnan 2010). These
types of nanocomposites are used as a carrier by utilizing the magnetic field.
Nanocomposites having biocompatible coatings help in preventing the aggregation and protects the body from toxicity also.
According to few reports, it was documented that for in vitro applications, biocompatible coatings are not necessary, and particles can be coated with nontoxic
materials.
Supermagnetic types of composites are made by surrounding the supermagnetic
nanocrystals in a non-magnetic matrix, for example, nanoporous silica or polystyrene (Leun and SenGupta 2000; Jain et al. 2008; Behrens 2011). Under the external
magnetic field, formed colloidal particles maintain the superparamagnetic behavior
and display higher magnetization.
NMs chemical composition constitutes of one or several materials. Naturally
formed NPs are often formed of materials agglomerations with different types of
compositions, whereas pure NMs having a single composition can be synthesized
in vitro using various methods.
There are basically different chemical orderings by which elemental atoms are
arranged within the NMs (Borbón 2011; Tiruvalam et al. 2011).
28
V. Dogra et al.