Nanotechnology is the manipulation of matter with at least one dimension sized from 0.1 to 100 nanometer,it's a brand new technology rise up from 1980s
The European Commission adopted the following definition of a Nanomaterial A natural,incidental or manufactured material containing particles,in an unbound state or as an aggregate or as an agglomerate and where,for 50% or more of the particles in the number size distribution,one or more external dimensions is in the size range 1-100 nm.
2,Properties of Nanomaterial
Nanomaterial is close to the scale of electron coherent length,which makes it own many unique properties. The melting point and conductive, magnetic, optical,thermal conductivity properties are very different compared to macro materials.
Quantum Size Effect
The quantum size effect referred to a phenomenon which could be observed when article size decrease to certain value, that is the electronic states near the Fermi level get band gab broden or turn to discrete energy levels from quasi continuous ones.
When diameter decreased, the particles' specific surface area increase significantly, thus atom ratio near the particle surface raise relatively. This cause to extremely high activity and instability of particle surface atoms, which leading to bunches of different characteristics. That above is so called surface effect. In the other hand, the surface layer atom density reduction creates many dangling bonds with unsaturation ; therefore the surface atoms demonstrate tremendous chemical activity and binding energy.
Scopic Quantum Tunnel Effect
Quantum tunnel effect is one of the basic quantum phenomena. When the total energy of the micro-particle is smaller than the barrier height, the particle is still able to penetrate the barrier. In recent year, it was discovered that some macroscopic quantities, such as micro-particle's magnetization and magnetic flux in quantum coherent devices, have the same effect, called macroscopic quantum tunnel effect.
3,Properties of Nanomaterial
Classification of Nano Materials
0D Nano Materials:Atom Cluster Structure, e.g. Nano Particle
1D Nano Materials:Fiber Structure, e.g.Nanowire, Nanotube
2D Nano Materials:Layered Structure, e.g. Nano Film
3D Nano Materials:Material with at least one dimension sized from 1 to 100 nanometer
Composite Nano Materials: Composites of 2 or more of above materials
Chemical Components: Nano Metal, Nano Crystal, Nano Ceramic, Nano Glass and Composite Nanomaterial
Applications: Nano Electric material, Nano Optoelectronic material, Nano Biomedical Material, Nano Sensitive Material, Nano Energy-storage Material and so on