CH250 Intermediate Analysis – Part 1Materials & Nanotechnology

Dr Raymond WhitbyC407

Overview

1. Defining nano

2. Formation of nanocarbon

3. Viewing the nanoscale; direct analysis

4. Indirect analysis of the nanoscale

5. Adsorption experiment

1. Defining nano

© iPod Nano© Tata Nano

Nanoscale

Ommatidia Lens

50nm

2nm

© Google images

“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!

Effects of gold on the nanoscale

© Yanfeng, et al., Journal of Semiconductors, Vol. 31, No. 1 January 2010

A model relating gold nanoparticle size and melting temperature for VLS grown silicon nanowire

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

Quantum confinements in dots

© Benoit Dubertret 2004 & Wikipedia on Quantum dots

“quantum dots are semiconductors whose conducting characteristics are closely related to the size and shape of the individual crystal. Generally, the smaller the size of the crystal, the larger the band gap, the greater the difference in energy between the highest valence band and the lowest conduction band becomes, therefore more energy is needed to excite the dot, and concurrently, more energy is released when the crystal returns to its resting state”

CdS

e qu

antu

m d

ots

Allotropes of carbon

Diamond

Coal

Graphite

© Google images

Nanocarbons 1985 to 1992

C60 – Buckminster fullereneSingle-walled carbon nanotube

Multi-walled carbon nanotube

1nm

© Google images

A reflection on size

Nanocarbon gallery

© Google images

Delocalised attraction of modified pyrene

Bio-molecule immobilisation

© H. Dai , JACS, 2001, 123 (16), pp 3838–3839

Ferritin covalently coupled to MWCNTs

Bio-molecule cross-linking

© Huang, et al., Nano Letters, 2002, 2 (4), pp 311–314

Carbon nanotube-enhanced thermal destruction of cancer cells in a noninvasive radiofrequency field

© Gannon, et al., Cancer. 2007 Dec 15;110(12):2654-65.

Cancer treatment

Enhancement of lipase activity in non-aqueous media upon immobilization on multi-walled carbon nanotubes

Can

dida

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osa

Lipa

ses

(CR

L) in

hyd

roly

sis

of p

-nitr

oph

enyl

palm

itate

© Shah, et al., Chem Cent J. 2007; 1: 30

Enzymatic activity enhancement

DNA sensor

© M. Meyyappan @ http://www.ipt.arc.nasa.gov

© Prof. Toru Maekawa, Toyo University, Japan

Magnetic manipulation

Nanocontact Manipulation

© www.nanotechnik.com

Carbon nanotube circuitry

Carbon nanotube advantages:1.Small diameter2.High aspect ratio3.Highly conductive along axis4.High mechanical strength5.High thermal conductivity

© M. Meyyappan @ http://www.ipt.arc.nasa.gov

© Easton-Bell Sports and www.zyvex.com

Carbon nanotube reinforcement

“the addition of Zyvex’s NanoSolve™ Materials to (Easton’s Stealth CNT) baseball bats strengthens composite structures to provide improved handle designs with optimized flex, responsiveness, and more ‘kick’...”

Commercial products

© Easton-Bell Sports

© Easton-Bell Sports

Multiwall carbon nanotubes enhance the fatigue performance of physiologically maintained methyl methacrylate–styrene copolymer

© Marrs, et al., Carbon, 2007, vol. 45, no10, pp. 2098-2104

Bone replacement material

Carbon nanofibres

Advanced uses

Carbon nanofibres

Advanced uses

Strengthening the future

© www.acceleratingfuture.com

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