1. Definitions

Nanoscience and nanotechnology can be defined as the science and technology of nanoscopic systems. The prefix "nano" refers to the nanometer (nm), or thousandth of a micrometer (or 10 ^-9 m). The systems under consideration have one or more dimensions between 1 and a few hundred nanometers. As a reminder, the typical radius of atoms is of the order of a tenth of a nanometer (0.1 nm = 1 Å). When particles have dimensions of the order of a nanometer or more, they are called nanoparticles.