Introduction to Nanomaterials Materials & Nanotechnology Dr Raymond Whitby

The Royal Society “We define (the nanoscale) to be from 100nm down to the size of atoms (approximately 0.2nm) because it is at this scale that the properties of materials can be very different from those at a larger scale”

Geometry Nanomaterials are materials that have a structural component smaller than 100 nanometers (nm) in at least one dimension x y z 100nm

Componentry At present there is no clear differentiation between nanomaterials and molecules, therefore, traditional chemistry can be viewed as a form of nanoscience. Single polymer strand atom cluster / particle benzene Deciding factors? Stability, chemical reactivity or inertness, solubility, inorganic materials?

Importance of nano (1) Two main reasons cause nanomaterial properties to significantly change from their bulk scale equivalents, those being an increase in the relative surface area and quantum effects. These can led to dramatic changes or enhancement of their fundamental properties such as material strength, electrical or thermal characteristics and heightened (bio)chemical reactivity. 30nm = 5% of atoms on surface 10nm = 20% of atoms on surface 3nm = 50% of atoms on surface N.B. not to scale!