Nanotechnology is the field of research and innovation concerned with building materials and devices – on the scale of atoms and molecules.
A nanometre is one-billionth of a metre: ten times the diameter of a hydrogen atom. The diameter of a human hair is, on average, 80,000 nanometres. At such a scale, the ordinary rules of physics and chemistry no longer apply. Material characteristics, such as colour, strength, conductivity, and reactivity, can differ substantially between the nanoscale and the macro. Carbon ‘nanotubes’ are 100 times stronger than steel but six times lighter.
Applications for Environmental Remediation
A variety of nanoscale materials with environmental applications have already been developed
Nanoscale materials can be used to remediate contaminated soil and groundwater at hazardous waste sites.
Nanoscale materials are of interest for environmental applications because the surface areas of the particles are large when compared with their volumes; therefore, their reactivity in chemical or biological surface-mediated reactions can be greatly enhanced in comparison to the same material at much larger sizes. Nanoscale materials can be manipulated for specific applications to create novel properties not present in particles of the same material at the micro- or macroscale. Because of their minute size, nanoscale materials may pervade very small spaces in the subsurface and remain suspended in groundwater if appropriate coatings are used. The appropriate coating may allow the particles to travel farther than macro-sized particles, achieve wider distribution, and therefore improve contaminant removal or reduction.