nanophysics lec (1)

1

Lec. (1)

Introduction to Nanophysics, Nanoscience and Nanotechnology

What is it?

2

Eigler et al. NATURE 363, 1993

How is nanoscience different than

• Chemistry

• Biology

• Physics

What distinguishes nanoscience from other sciences?

Nanoscience and nanotechnology are the study and application of extremely small things and can be used across all the other science fields, such as chemistry, biology, physics, materials science, and engineering.

What is Nanophysics, Nanoscience and Nanotechnology?

3

Richard Feynman is the father of nanotechnology. with a talk entitled “There’s Plenty of Room at the Bottom” at an American Physical Society meeting at the California Institute of Technology (CalTech) on December 29, 1959, long before the term nanotechnology was used.

Physicist Richard Feynman

Feynman described a process in which scientists would be able to manipulate and control individual atoms and molecules.

Over a decade later, in his explorations of ultraprecision machining, Professor Norio Taniguchi coined the term nanotechnology. It wasn't until 1981, with the development of the scanning tunneling microscope that could "see" individual atoms, that modern nanotechnology began.

4

STM

5

is an instrument for imaging surfaces at the atomic level. Its development in 1981 earned its inventors, Gerd Binnig and Heinrich Rohrer (at IBM Zürich), the Nobel Prize in Physics in 1986For an STM, good resolution is considered to be 0.1 nm lateral resolution and 0.01 nm depth resolution.[3] With this resolution, individual atoms within materials are routinely imaged and manipulated. The STM can be used not only in ultra-high vacuum but also in air, water, and various other liquid or gas ambients, and at temperatures ranging from near zero kelvin to a few hundred degrees Celsius.[4]

The STM is based on the concept of quantum tunneling. When a conducting tip is brought very near to the surface to be examined, abias (voltage difference) applied between the two can allow electrons to tunnel through the vacuum between them. The resulting tunneling current is a function of tip position, applied voltage, and the local density of states (LDOS) of the sample.[4] Information is acquired by monitoring the current as the tip's position scans across the surface, and is usually displayed in image form.

A scanning tunneling microscope (STM)

PLAR - Nanotechnology

Nanotechnology is the creation of functional materials, devices, and systems through control of matter on an atomic or molecular scale.

The creation and use of structures, devices and systems that have novel properties and functions because of their small and/or intermediate size.

DEFINITION OF NANOTECHNOLOGY

Nano: The Middle Ground

Gal

acti

c

“Mac

rosc

op

ic”

“Mic

rosc

op

ic”

“Nan

osc

op

ic”

Mo

lcu

lar/

Ato

mic

Sca

leS

ub

ato

mic

/Nu

clea

rP

arti

cle? ?

10 20 m

10 10 m10 1 m

10 -6 m10 -9 m

10 -15 m10 -10 m

?

UNIQUENESS OF NANOMATERIALS

• Grains, pores, interface thickness and defects are of similar dimensions.

• Nanomaterials have a large surface area but their volume is very small.

• Improve mechanical properties (increased strength, toughness etc.,)

• High melting point compounds.

INTERDISCIPLINARY APPROACH REQUIRED

10

nanotechnology were developed for many current

challenges facing the international community, including:

• Clean, secure, affordable energy;

• Stronger, lighter, more durable materials;

• Low-cost filters to provide clean drinking water;

• Medical devices and drugs to detect and treat diseases more

effectively with fewer side effects;

• Lighting that uses a fraction of the energy associated with

conventional systems;

• Sensors to detect and identify harmful chemical and

biological agents; andTechniques to clean up harmful

chemicals in the environment.

FIELDS OF NANOTECHNOLOGY

Nanotechnology

Nanomedicine

Nanobiotechnology

Nanolithography

Nanoelectronics

Nanomagnetics

Nano Biodevices

NEMS (nano electro mechanical sys)

Nano Biomimetic materials

Nano Pulp & Paper Technology

Applications of NanomaterialBased Products

Automotive industryEngineeringMedicine CosmeticsTextile SportsChemical industryElectronic industry

13

• ExxonMobil is using zeolites, minerals with pore sizes of less than 1 nm, as a

more efficient catalyst to break down or crack large hydrocarbon molecules to

form gasoline.

• IBM has added nanoscale layering to disk drives, thus exploiting the giant

magnetoresistive effect to attain highly dense data storage.

• Gilead Sciences is using nanotechnology in the form of lipid spheres, also known

as liposomes, which measure about 100 nm in diameter, to encase an anticancer

drug to treat the AIDS-related Kaposi’s sarcoma.

• Carbon Nanotechnologies, a company co-founded by buckyball discoverer

Richard E. Smalley, is making carbon nanotubes more affordable by using a new

and more efficient manufacturing process.

• Nanophase Technologies is utilizing nanocrystalline particles, incorporated into

other materials, to produce tough ceramics, transparent sun blocks, and catalysts

for environmental uses, among other applications.

Applications of Nanotechnology in industrial and technical fields:

14

The Space Elevator?

Ultra high strength materials allow tower to be built into space !(?)

What is Nanotechnology?

15

Tiny machines in your body curing cancer?

What is Nanotechnology?

16

DNA Computers in a beaker that vastly outperform our fastest supercomputers?

What is Nanotechnology?

17

Nanotechnology

TECHNOLOGIES

Nanomaterials

Nanolithography

Scanning Probe

Microscopy

Self-Assembly

APPLICATIONS

Super fast/small computers

Super strong materials

Super Slippery Materials

Tissue Engineering

Drug Delivery

Sensors

18

Materials Science: Nanomaterials

Human Made Materials

Biologicallymade materials

19

Calcium phosphate

HydroxyapatiteCalcite

Silica Calcium Carbonate

20

Superhydrophobic Surfaces:The Lotus Effect

NANO- TEXTILE APPLICATIONS

Nano Jacket

Student’s uniform

Nano tie and scarf

Atlantic – Aprilia fuel cell bikePhotovoltaic cell

Fuel Cell

NANOTECHNOLOGY – FUEL CELL

Hydrogen

23

Carbon Nanotubes

CHIN WEE SHONG : AgS2 cubesNational University of SingaporeDepartment of Chemistry

Quantum dots

24

Carbon NanotubesBuckminster Fullerene C60

Smalley, Curl, Kroto. Nobel Prize

25

Graphein: (Greek) to write

Graphite

Diamond

Nanotube

Buckyball

The Forms of Carbon

26

What’s the big deal about carbon nanotubes???

• Amazing Mechanical Properties

• Amazing Electrical Properties: – Can be conductors or semiconductors– Could be the building block of nanocomputing

27

Applications:Composite Materials

nanotubes poking out of fractured edge of polymer composite

28

Applications: Field Emission 1

Samsung prototype carbon nanotube display

29

Otto Zhou. UNC Physics

Cold Cathode X-ray machine

The potential advantages of the future CNT X-ray devices are fast response time, programmable xrayintensity, programmable spatial distribution (Figure 3), ultra-fine focal spot, rapid pulsationcapacity, long lifetime, low energy consumption, miniaturization, and low cost.

Applications: Field Emission 2

30

Quantum Dots

31Polydimethylsiloxane (PDMS)

Synthesis of Nanomaterials

Top - down method (Destruction)

Bottom-up method (Construction)

Synthesis of Nanomaterials

Top - Down method

High energy Ball Milling Lithography Gas

condensation Severe plastic deformation

Synthesis of Nanomaterials

SYNTHESIS OF NANOMATERIALS

Bottom Up

method

Physical Vapor

Deposition

Chemical Vapor

Deposition

Plasma Processes

Sol-gelProcessing

Soft-Lithography

Self-Assembly

CHARACTERIZATION AND DETECTION TECHNIQUES

• Essential requirements for the development, manufacturing and commercialization of nanomaterials is their physical, chemical and biological properties on a nanoscale level

• For determination of atomic structure and chemical composition of solid or liquid nanomaterials – spectroscopic methods, X-ray and Neutron diffraction

• For determination of size and shape – Electron microcopies (SEM or TEM)

Optical Microscope Scanning Electron Microscope

HIGH DEPTH OF FIELDNANOMATERIAL

transmission electron microscope

WORKING PRINCIPLE OF AFM

www.shef.ac.uk/~htsl/afm.htm

Atomic Force MicroscopeForce

Surface Atoms

Tip Atoms

Photo detector

Laser Beam

Tip

Cantilever

Line Scan

Surface