Why Nano?

The word 'nano' comes from the Greek for dwarf, though the actual nanometre scale is, in the chapter's own words, even smaller than what 'dwarf' might suggest. Conventionally, the nanometre scale is defined as running from 1 to 100 nanometres (nm), where one nanometre is one-billionth of a metre (1 nm = 10^-9 m). The materials seen and handled in everyday life are bulk materials, possessing macroscopic physical properties; even a grain of sand, though micron-sized and far smaller than an everyday object, still shows those same bulk properties. But a material synthesised specifically at the nanoscale (1-100 nm) possesses unique optical, structural, thermal, catalytic, magnetic and electrical properties that are simply not present in the bulk form of the same substance -- these properties change as a direct function of particle size, and are very different from the properties of the corresponding bulk material. This size-dependent change in fundamental properties is exactly …