Nanomaterials: Classification and Properties

Nanoparticles have all the three dimensions in the nanometer range, nanoplates present only one dimension below 100 nm, whereas nanofibers have two dimensions in the range of nano being the remaining remarkably longer. A constantly growing number of applications of engineered nanomaterials are reported in cosmetics, sporting wear and goods, tires, electronics, and medicine. It is accepted that nanomaterials can be produced by physical, chemical, or bio-based methods. The most relevant physical properties to be monitored are size, shape, specific surface area, physical state, capability for aggregates via self-assembly, size distribution, smoothness of the surface, crystal structure, and facility to dissolve in solvents. The chemical properties such as: molecular structure, presence of impurities or additives, surface chemistry, and interaction with water or other solvents are considered. The main purpose of the Environmental Protection Agency comprehensive regulatory approach is to avoid unreasonable risks to health and environment with the manufacturing and use of nanomaterials.