Nanomaterials mean that at least one dimension of the three-dimensional space is in the nanoscale（1nm-100nm）or materials that they form as basic units. This refers to the change in properties caused by the sharp increase of the ratio of atomic number to total atomic number on the surface of nanocrystals with the decreasing particle diameter. For example, when a particle is 10 nanometers in diameter, it contains 4,000 atoms, There are 40% atoms on the surface; The particle contains 30 atoms and 99% atoms on the surface when the particle diameter is 1 nanometer.
Nanoscale structural materials are referred to as nanomaterials，It refers to the size of the structural unit between 1 nanometer and 100 nanometer. Because its size is close to the coherent length of the electron, It’s properties change greatly because of the self-organization caused by strong coherence. The size length of nanomaterials is close to the wavelength of light and it has the special effect of large surfaced, therefore, the characteristics of its performance, For example, melting point magnetism, optics, thermal conductivity, and so on, It’s often different from what the substance appears to be in its overall state.
Nanomaterials are also called ultrafine granular materials. It's made up of nanoparticles. Nanoparticles are also called ultrafine particles. It generally refers to particles between 1 and 100nm in size. It is a transitional region at the junction of a cluster of atoms and a macroscopic object. From the usual micro and macro point of view, Such systems are neither typical microscopic systems nor typical macroscopic systems ,.It is a typical mesoscopic system. It has surface effect small size effect and macroscopic quantum tunneling effect. When people subdivide a macroscopic object into ultrafine particles, it will show many wonderful properties That is, its optical, thermal, electrical, magnetic, mechanical, and chemical properties are going to be significantly different than they would be if it were a bulk solid.