Nanotechnology | Classification of Nanomaterial
In recent years, nanotechnology has become attractive and most important technology for researchers due to a lot of application in different fields of life. In the twenty-first century, nanotechnology has become more important in different fields like material science, biological science, medicine, and electronics.
The dimensional range of nonmaterial lies between 0.1 and
100nm (1nm=10 ^-9 m). Nanoscale is much smaller then micro level approximately
1000 times, and 10^9 times Smaller than common measuring things. Nanotechnology
is vast field for scientist and researchers and they are trying to make
different Nanoscale materials with high efficiency (Granqvist, 2013).
Nanotechnology was named later on but this technology
existed and was researched many years ago. The term ―nano‖ browed from Greek
word Nano which means tiny. The famous and prominent Scientist ―Richard Feynman
―introduced the concept of nano’s technology in 1959 at annual meeting of
California Institute of Technology. His topic was ―there’s plenty of room at
the bottom‖ . He also suggested that we can arrange atoms according to our own
desired, but term nanotechnology was introduced by ―Norio Taniguchi‖ in 1974 he
was inspired by Feynman.
ZnS photocatalysts
Nanomaterials:
Scientists are not completely agreed to any single
definition of nanomaterial, but they agree to its tiny size in nanometer range
.The diameter of human hair is approximately 10^5 larger than a nanometer.
Thus, its size must be under the range of 100 nm. Due to such smaller diameter
nanomaterial show dramatic change in different properties like electrical,
thermal, magnetic and mechanical properties. We prefer nanomaterial due to many
peculiar reason and the few are discussed blow.
- These materials have larger surface area to volume ratio as compared to same mass of bulk materials.
- Nanomaterials are more reactive as composed to bulk form of materials due to smaller size.
- In nanomaterial the interior atoms have high concentrations which increase the thermal properties.
- When we reduced the bulk materials into nano rage forbidden energy gaps increase and the conductivity of nanomaterials decrease (Granqvist, 2013).
Figure 1.1 Schematic representations of nanoparticles |
Classification of Nanomaterials:
In previous few decades many Nanomaterials have been
discovered. Due to lot of research on nanomaterial, the classification of
nanomaterial has become more necessary for this purpose first attempt was made
by Glitter in 1995 and Skorokhod finalized this approach in 2000.
Zero Dimensional (0D) Nanomaterials:
0D nanomaterial has get extensive attraction of researcher
due to many novel properties like quantum confinement effect, excellent
chemical and physical properties, ultra small size and biocompatibility.
In zero dimensional (0D) nanomaterial including carbon
quantum dots, imaging quantum dots, inorganic quantum dots, magnetic
nanoparticle, Nobel metal particle all these types attracted extensive
attraction of researchers due to lot of application in different field of life,
we get zero dimensional structure by changing the size of nonmaterial. The zero
dimensional material (0D) has dramatic properties as compare to higher
dimensional material. No one dimension of nano material outside nanorange and
all ranges lies in nanorange common example of zero dimensional nanomaterial is
quantum dots, colloids, nanoparticle (Tiwari, Tiwari, & Kim, 2012).
One Dimension (1D) Nanomaterials:
Material which has one dimension out of nanorange and all
other dimension are in nanorange are called one dimension nano material (1D).
These materials have lot of application in energy storage field. These
materials have dramatic properties like electrical, chemical, mechanical and
magnetic properties due to large height-width ratio (Visakh & Morlanes,
2016).
The subgroups of one dimension nanomaterials are silicone,
carbon, conducting composite and metallic oxide. One demotion nano material is
more popular than two dimensions (C. Chen et al., 2018). One dimension
nanomaterials mostly used in supercapacitor and batteries. Silicon is mostly
used in energy storage devices due to high theoretical capacity also used as
nanotubes nanowires and nanorods. The carbon has unique size excellent
electrical properties as well as efficient energy storage capacity.
Metalloids are more important one dimension nano materials
mostly used in energy storage purpose and supercomputer (Salerno, Landoni,
& Verganti, 2008).
Two Dimension (2D) Nanomaterials:
The two dimension nanomaterials (2D) have two dimensions out
of nano-range and one dimension in nanorange. In past two dimension
nanomaterial in the form of layered structure get great interest in both
academic and industrial field .In two dimension nanomaterials (2D) the atom on
surface ratio is high therefore these material show unique behavior. Most
important and widely used two dimension material is Graphene. Graphene has
unique properties other than two dimension nanomaterials like hexagonal boron
nitride, metal dichalcognide etc. Other two dimension nanomaterial shows such
properties but is not easy to use such as graphene, therefore we prefer
graphene.
Two dimension nanomaterials have a high aspect ratio, larger
surface area, and large number of atoms on surface these characteristics of two
dimensions nanomaterials changed the properties such as thermal, electrical
conductivity and mechanical. Due to these characteristics the demands of two
dimension nanomaterials increase in the fields of coating, electrical and
electronic devices (S. Liu, Pan, & Liu, 2020).
Three Dimension (3D) Nanomaterials:
Three dimension nanomaterials are those in which not any
dimension in nanorange and all three dimension out of nano range, best example
of nanomaterials are bundle of nanowire, nanotubes etc. Most important two
dimension nanomaterial graphene has unique properties and lot of application in
many fields of science and technology (Ginting & Malau, 2022).
Now time three dimension graphene attain more attention
because the two dimension properties because include as intrinsic properties.
Three dimension graphene is most preferable used in supercapacitor due to
excellent electrical conductivity, large surface area and unique mechanical
characteristics (Popkov, Tolstoy, & Semenov, 2020).