“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 polymer strand 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!
As matter is reduced in size, quantum effects can become the dominant factor of a material’s properties. This is particularly evident when approaching the smaller end of the nanoscale. Importance of nano (2) “The harmonic oscillator and the systems it models have a single degree of freedom. More complicated systems have more degrees of freedom, for example two masses and three springs (each mass being attached to fixed points and to each other). In such cases, the behavior of each variable influences that of the others. This leads to a coupling of the oscillations of the individual degrees of freedom. For example, two pendulum clocks (of identical frequency) mounted on a common wall will tend to synchronise. This phenomenon was first observed by Christaan Huygens in 1665.” Wikipedia
Questions on nano 1.What is the definition of the nanoscale? What about nanomaterials? 2.Describe the differences between atoms and nanomaterials? 3.What is the difference between nanoscience and nanotechnology? 4.Which area of science is the best to invest in for nanotechnology enhancement?
All material under copyright was scanned under a CLA licence