Synthesis of nanostructured materials

Nanotechnology and nanomaterials are now interesting subjects of mankind. Generally any material whose dimension ranges 0.1 to 100 nm is called as nanomaterials. Quantum dots are zero dimensional, multilayers (Quantum wire) are one dimensional, ultrafine grained over layers or buried layers (Quantum well) are two dimensional equiaxed nanometer sized grains are three dimensional nanomaterials. There exist two steps for the synthesis of nanostructured materials- top-down and bottom-up. Examples of top-down methods are mechanical alloying or milling, lithography and erosion. Examples for bottom-up methods are chemical coprecipitation, gas phase agglomeration, sol gel, reverse micelles, physical and chemical vapour deposition, sputtering and self assembly.