2 Nanotechnology
Applications of nanoparticles can be seen in almost every field of science like
automobiles, cosmetics, agriculture, food, textiles, space, defense, engineering,
medical fields, and environment. According to the US National Nanotechnology
Initiative (NNI), nanotechnology is defined as “the understanding and control of
matter at dimensions between approximately 1–100 nanometres, where unique
phenomena enable novel nanotechnology applications.” Encompassing nanoscale
science, engineering, and technology, nanotechnology involves imaging, measuring,
modeling, and manipulating matter at this length scale. In the past few years, use of
nanotechnology in contaminant removal has become prominent due to its small
particle size, high surface area to volume ratio, easy injection to the site of action,
flexibility for in situ and ex situ application, etc.
2.1 Shapes, Sizes, and Structures
Nanotechnology basically deals with particles having dimensions within 1–100 nm
range and forms the functional systems that can be used to solve a problem or
perform a specific function. Different properties of nanoparticles like its reactivity,
magnetism, stability, and optical characteristics depend on the distinctive size,
shape, and structure of the nanoparticles. These characteristics of nanoparticles
make them suitable candidates in different fields of application like drug delivery,
textiles, cosmetics, water purification, food packaging, and several other industrial
uses. The nanoparticles can be synthesized in different shapes like rods, spheres,
cubes, triangles, polygons, etc., and depending on their shapes, the nanoparticles are
named as nanospheres, nano-rods, nano-cubes, etc. (Wu et al. 2016). The structure of
the nanomaterials can be organized with respect to their dimensions. The
nanomaterials are mostly found in zero dimension, e.g., fullerenes, atomic clusters;
one dimension, e.g., nanofibers and nanowires; or two dimensions, e.g., nanodisks,
nanolayers, etc. (Benelmekki 2015).
2.2 Synthesis and Characterization
There are mainly two approaches for the synthesis of nanoparticles. One is top-down
approach and the other is bottom-up approach. When a larger system breaks down to
form nanosized particles, it is known as top-down approach such as high energy ball
milling, grinding, etching, laser pyrolysis, lithographic techniques, etc., whereas in
bottom-up approach, atoms combine to form clusters, and these clusters aggregate to
7 Nano-bioremediation: An Innovative Remediation Technology for Treatment. . .
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Applications of nanoparticles can be seen in almost every field of science like
automobiles, cosmetics, agriculture, food, textiles, space, defense, engineering,
medical fields, and environment. According to the US National Nanotechnology
Initiative (NNI), nanotechnology is defined as “the understanding and control of
matter at dimensions between approximately 1–100 nanometres, where unique
phenomena enable novel nanotechnology applications.” Encompassing nanoscale
science, engineering, and technology, nanotechnology involves imaging, measuring,
modeling, and manipulating matter at this length scale. In the past few years, use of
nanotechnology in contaminant removal has become prominent due to its small
particle size, high surface area to volume ratio, easy injection to the site of action,
flexibility for in situ and ex situ application, etc.
2.1 Shapes, Sizes, and Structures
Nanotechnology basically deals with particles having dimensions within 1–100 nm
range and forms the functional systems that can be used to solve a problem or
perform a specific function. Different properties of nanoparticles like its reactivity,
magnetism, stability, and optical characteristics depend on the distinctive size,
shape, and structure of the nanoparticles. These characteristics of nanoparticles
make them suitable candidates in different fields of application like drug delivery,
textiles, cosmetics, water purification, food packaging, and several other industrial
uses. The nanoparticles can be synthesized in different shapes like rods, spheres,
cubes, triangles, polygons, etc., and depending on their shapes, the nanoparticles are
named as nanospheres, nano-rods, nano-cubes, etc. (Wu et al. 2016). The structure of
the nanomaterials can be organized with respect to their dimensions. The
nanomaterials are mostly found in zero dimension, e.g., fullerenes, atomic clusters;
one dimension, e.g., nanofibers and nanowires; or two dimensions, e.g., nanodisks,
nanolayers, etc. (Benelmekki 2015).
2.2 Synthesis and Characterization
There are mainly two approaches for the synthesis of nanoparticles. One is top-down
approach and the other is bottom-up approach. When a larger system breaks down to
form nanosized particles, it is known as top-down approach such as high energy ball
milling, grinding, etching, laser pyrolysis, lithographic techniques, etc., whereas in
bottom-up approach, atoms combine to form clusters, and these clusters aggregate to
7 Nano-bioremediation: An Innovative Remediation Technology for Treatment. . .
167