Abstract:
The prefix nano in ‘nanoscience’ means a billionth (1 × 10-9
). It deals with various aspects of
matter, having dimensions of the order of a billionth of a meter (1 nm). At the nanoscale, the
fundamental properties of materials depend on their size, shape, and composition. When objects are
below 100 nms in size, they tend to exhibit unusual chemical and physical properties Comparisons of objects are having different sizes from micrometer to nanometer [From
ref 1].
For example, ZnO, an important semiconducting and piezoelectric material can be obtained
in various shapes such as tubes, wires, rings and even other exotic forms such as springs, combs, belts
and cages in nm range. Besides spherical nanoparticles of metals and semiconductors and carbon
nanotubes [2, 3], other interesting shapes include nanotriangles, nanocubes, mesoflowers,
nanoprisms, nanodisks and nanorings, junction nanotubes, nanowalls, nanoflowers etc. Such shapes
may be derived from metals, semiconductors, oxides, nitrides, sulfides etc. Figure 1.2 shows electron
micrographs of some interesting shapes of nanoobjects [4-10].
