Introduction to NanomaterialsMaterials & Nanotechnology

Dr Raymond Whitby

“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”

The Royal Society

Geometry

x

y

z

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

100nm

Componentry

atom cluster / particle

Single polymerstrand

benzene

At present there is no clear differentiation between nanomaterials and molecules, therefore, traditional chemistry can be viewed as a form of nanoscience.

Deciding factors? Stability, chemical reactivity or inertness, solubility, inorganic materials?

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.

Importance of nano (1)

30nm = 5% of atoms on surface

10nm = 20% of atoms on surface

3nm = 50% of atoms on surface

N.B. not to scale!