Synthesis and Characterisation of Nanomaterials
The objective of any engineered technique for preparation of nanoparticles is to fabricate nanomaterials which have the unique properties for applications that are a result of their characteristic length scale being in the nanometer run (1 – 100 nm). Likewise, the manufactured strategy should show control of size in this range with the goal that one or the other property can be attained. There are two general strategies for synthesis of nanomaterials and the fabrication of nanostructures: “Bottom Up” and “Top Down”.
Bottom up approach refers to the build-up of a material from the bottom: start with atoms or molecules and build up to nanostructures. The starting material is either gaseous state or liquid state of matter for bottom up method.
Top down approach refers to cutting of a bulk material to get nano sized particle: begin with a pattern generated on a larger scale, then reduced to nanoscale. The starting material is in solid state for top down method.