Nanomaterials are materials possessing grain size of the order of a billionth of a meter. They manifest extremely fascinating and useful properties, which can be exploited for a variety of structural and non-structural applications.
Nanoparticles behave quite different from their coarser-grained counter parts of the same composition due to the high surface to volume ratio.
Simply, nanomaterials are those which has one of their dimension ( length, thickness or both) between 1 and 100 nanometers. In this dimension, the physical properties of the materials will be different from that of their bulk as the surface effects play a major role.
Bulk materials properties are constant wit respect to size.but below a certain size nanomaterials are having size dependent physical and chemical and other properties. for example if u take iron its melting point is 1538 degrree C for bulk.But in the nano below a certain size its melting point varies with respect to size i.e its reduces as the size decreases.similarly all the other properties vary according to the size.
Any 3-D object which has one of its dimension in the range of 1-100nm are nanomaterials, but the bulk materials have larger one or more dimension, Due to this the basic properties varies due its surface to volume ratio
Nanotechnology is the understanding and control of matter at dimentions between approximately 1 to 100 nanometers , where unique phenomenoa enable novel applications .
In nanomaterials (1) Large fraction of surface atoms; (2) High surface energy; (3) Spatial confinement; (4) Reduced numbers of imperfections that do not exist in the corresponding bulk materials
Properties of the Bulk material is independent of its size. When the particle once reduces to nano size its properties fully dependence on its size