Nanoparticles: Building Blocks for Nanotechnology

摘要

Nanoparticles are defined as particles with size in the range of1 to 100 nm at least in one of the three dimensions. Becauseof this very small size scale, they possess an immense surfacearea per unit volume, a high proportion of atoms in the surfaceand near surface layers, and the ability to exhibit quantumeffects. The resulting unique properties of nanoparticlescannot be anticipated from a simple extrapolation of theproperties of bulk materials. Nanoparticles exist with greatchemical diversity in the form of metals, metal oxides,semiconductors, polymers, carbon materials, organics orbiological. They also exhibit great morphological diversitywith shapes such as spheres, cylinders, disks, platelets, hollowspheres and tubes, etc. Nanoparticles can be generated via anumber of synthetic routes based on gas, liquid or solid phaseapproaches. The synthesized nanoparticles have to be surfacemodified in most cases, in order to passivate and stabilize themsince their nanoscale renders them chemically very reactiveand/or physically aggregative. The nanoparticles are alsosurface functionalized in order to meet the needs of specificapplications. Nanoparticles serve as the fundamental buildingblocks for various nanotechnology applications.