Extreme Physics : very small things - The Nanoworld Done by Ong Beng Hwee.

Extreme Physics : very small things - The Nanoworld

Done by Ong Beng Hwee

What is the nanoworld?

The sphere of influence or the world at a microscopic level, as dealt with by nanotechnology

Where everything is 1/1000000000 the original size

Nanoworld revolves around nanotechnology and nanoparticles

What is nanotechnology? Nanotechnology, refers to the branch of

engineering dealing with things smaller than 100 nanometers

Nanotechnology is very diverse, ranging from extensions of conventional device physics to completely new approaches based upon molecular self-assembly, from developing new materials with dimensions on the nanoscale to investigating whether we can directly control matter on the atomic scale

What is a nanoparticle?

A nanoparticle is defined as a small object that behaves as a whole unit in terms of its transport and properties

Nanoparticles may exhibit size-related properties that differ significantly from those observed in fine particles or bulk materials

History of Nanotechnology First mentioned in 1959 by Richard Feynman

Developed in 1980s-90s

"The revolutionary Feynman vision launched the globalnanotechnology race.“ -Eric Drexler

Nanotechnology when it first began First introduced in 1959 by Richard Feynman, a

physicist at Caltech, during a talk called "There's Plenty of Room at the Bottom

Feynman suggested precisely manipulating atoms and molecules to create "nano-scale" machines, using a cascade of billions of factories

These factories would be progressively smaller scaled versions of machine hands and tools which would then eventually be able to create billions of tinier factories

He suggested that as the scale got smaller and smaller, gravity would become more negligible, while both Van Der Waals attraction and surface tension would become very important

Development in 1980s to 1990s The term "nanotechnology" was coined

Eric Drexler and other researchers, built up this field from the foundation of Feynman

Drexler founded the Foresight Institute, whose stated goal is to ensure the beneficial implementation of nanotechnology to present his vision of molecular manufacturing

"Molecular Assemblers will bring a revolution without parallel since the development of ribosomes, the primitive assemblers in the cell. The resulting nanotechnology can help life spread beyond Earth - a step without parallel since life spread beyond the seas; it can let our minds renew and remake our bodies - a step without any parallel at all."-Eric Drexler

Don Eigler manipulated individual Xenon atoms on a Nickel surface to form the letters "IBM"

Advancing the field of nanotechnology by seeking to simply manipulate atoms

Why is the Nanoworld important?

Nanotechnology has the potential to change every part of our lives

Nanotechnology affects all materials: ceramics, metals, polymers, and biomaterials

New materials are the foundation of major technological advances

Why is the Nanoworld important?(con’t)

Future advances could change our approaches to manufacturing, electronics, IT and communications technology making previous technology redundant

By building things at the nanoscale, people work with individual atoms or a handful of atoms and can take advantage of the different properties of nanoparticles

What actually happens when objects turn small?

Objects usually have constant physical properties regardless of its size, but at the nano-scale size-dependent properties are often observed

Properties of materials change as their size approaches the nanoscale as there is a vast increase in ratio of surface area to volume

For materials larger than one micrometer, the percentage of atoms at the surface is insignificant in relation to the number of atoms in the material

Gold

Gold is a shiny, yellow noble metal that does not tarnish, has a face centered cubic structure, is non-magnetic and melts at 1336 K.

Nanogold

Nanogold, or colloidal gold, is a suspension of sub-micrometre-sized particles of gold in a fluid.

Usually either an intense red colour, or a dirty yellowish colour.

Properties of nanogold At 10 nm particles absorb green light and appear red Melting temperature decreases dramatically. Ceases to be noble, and 2-3 nm nanoparticles are

excellent catalysts which also exhibit magnetism. At this size they are still metallic, but smaller ones

turn into insulators.

Con’t

When it is shrunk to exactly 3 to 5 nm in size, resuming inertness when not in the range.

Equilibrium structure changes to icosahedra symmetry, or they are even hollow or planar, depending on size.

Substantional bond contraction occurs at outermost two atomic shells; the catalytic ability increases by several folds.

Why? Caused by the broken bond induced local

strain and quantum trapping and the associated densification of charge and energy in the surface skin are responsible for the size induced behavior.

The shorter and stronger bonds in the surface skin lowers the energy levels of the electrons and enhance the electronegative.

Less-coordinated atoms more electronegative.

Application (catalyst)

Conversion of carbon-monoxide to carbon-dioxide

Nanogold catalyzes this at room temperature and with 100% efficiency.

Capable of aiding firefighters, who now wear protective masks containing copper-manganese-oxide, getting rid of CO for 15 minutes, while nanogold protects for several hours.

Application of nanogold

Detection for cancer

Treatment for cancer

Detection for cancer 1)Identifies proteins on the exteriors of cancer cells 2)Use specialized antibodies to latch onto the protein

markers for the cancer type. 3)After the nanorods bind to proteins in a blood

sample, scientists examine how they scatter light. Each protein-nanorod combination scatters light in a unique way, allowing for precise diagnoses.

1)Cheaper 2) Earlier diagnosis 3)Does not require a biopsy.

Treatment for cancer

Method: Load cancer-detecting gold nanoparticles with

anticancer drugs, capable of attacking the cancer exactly where it lives.

Benefits: Fewer side effects and less medication used. These treatments aim to take advantage of the power

of nanotechnology and the voracious tendencies of cancer cells, which feast on everything in sight, including drug-laden nanoparticles.

Other ways of usage in cancer treatment

Nanogold sucked up by cancer cells, heated with a magnetic field to weaken them, making them more susceptible to chemotherapy.

Using phthalocyanine, which reacts with light, nanogold takes the dye directly to cancer cells while normal cells reject the dye.

Once the particles are inside, scientists "activate" them with light to destroy the cancer.

Negative effects

Nanoparticles' small size allows them to infiltrate anywhere.

Potentially harmful to healthy cells and DNA. No method of disposing nanoparticles used in

manufacturing or other processes. Harmful particles may end up in the water

supply or in the general environment.

Interesting facts!

1) Drexler had also associated nanotechnology

as being one of a possible scenario of the end of the world.

“Gray Goo” An amalgamation of self-replicating nanobots that would consume everything in the universe in order to survive

2) Nanoaluminium explodes at 30nm!!

About Fact 1…

"In a common practice, billions of nanobots are released to clean up an oil spill off the coast of Louisiana. However, due to a programming error, the nanobots devour all carbon based objects, instead of just the hydrocarbons of the oil. The nanobots destroy everything, all the while, replicating themselves. Within days, the planet is turned to dust.“ -Drexler

"There's no limit to the number and variety of self-assembled nano-materials you can make."

Brief benefits of Nanotechnology in our lives

Nanotechnology in Battery Reduce the possibility of batteries catching fire via

flammable electrode material. Increasing the battery’s electrical by coating the

surface of an electrode with nanoparticles. This increases the surface area of the electrode thereby allowing more current to flow between the electrode and the chemicals inside the battery.

Increase the shelf life of a battery by using nanomaterials to separate liquids in the battery from the solid electrodes when inactive

Battery with silicon nanowires that can: 1)increase the capacity of Li-ion batteries 2)Small enough to be implanted in the eye

and power artificial retina 3)Improves performance of cars. 4)With titanium disilicide lattice, may improve

the discharge rate of Li-ion batteries and battery lifetime.

Nanotechnology in Fabric

Nano-sized fibers allows improvement of fabric properties without significant increase in weight, thickness, or stiffness as might have been the case with previously-used techniques.

Silver nanoparticles in fabric that kills bacteria making clothing odor-resistant.

Provides superior insulation for shoe inserts in cold weather.

Nanotechnology in Solar cells

Cheaper as: 1)Production releases little heat;no

need to cool down machines. 2)Produces flexible rolls. 3)Titanium dioxide nanotubes filled with

a polymer 4) Organic molecules used.

Increased efficiency due to:

1)Combining lead selenide quantum dots with titanium dioxide

2)Combining carbon nanotubes, bucky-balls and polymers can be formed by simply painting a surface.

Nanotechnology in Space

Use of bio-nano robots in spacesuits, responding to damages to the spacesuit or provide drugs in a medical emergency.

Deploying a network of nanosensors to search large areas of planets such as Mars for traces of water or other chemicals.

Using carbon nanotubes to reduce the weight of spaceships while retaining or even increasing the structural strength.

Nanotechnology in food To prevent contamination: 1)Clay nanocomposites in food containers to provide

impermeable membrane 2)Containers coated with silver nanoparticles. Silver

nanoparticles kills harmful bacteria. 3) Nanosensors to detect contamination. 4) Zinc oxide nanoparticles incorporated into plastic

packaging block UV rays, provide anti bacterial protection improves the strength and stability.

5)Nanocapsules that contain flavor or color enhancers are embedded in the food; inert until a hungry consumer triggers them.

Super Vitamins

Nanoparticles can… 1)deliver vitamins or other nutrients in food

and beverages without affecting the taste or appearance by encapsulating the nutrients and carry them through the stomach into the bloodstream.

2) Use nanosensors to detect a vitamin deficiency which delivers the nutrients you need, when you need them.

Water related Nanoparticles used to .. 1)Deionize using electrodes composed of nano-sized fibers,

reducing the cost and energy requirements of turning salt water into drinking water.

2)A filter nanometers in diameter is capable of removing virus cells from water.

3) Iron nanoparticles to clean up carbon tetrachloride pollution in ground water, , clean arsenic from water wells and neutralize dense, hydrophobic solvents polluting ground-water

4)Using silver chloride nanowires as a catalyst to decompose organic molecules in polluted water.

5)Absorb radioactive particles polluting ground-water 6)Using gold tipped carbon nanotubes to trap oil drops

polluting water

Air pollution 1)Catalyses harmful vapors escaping from cars or

industrial plants into harmless gasses with greater efficiency as nanoparticles have a greater surface area to interact with the reacting chemicals than catalysts made from larger particles simultaneously.

2)Gold nanoparticles embedded in a porous manganese oxide catalyse to breakdown volatile organic compounds in air.

3)Using crystals containing nano sized pores to trap carbon dioxide. Then converting carbon dioxide to biofuel

Thank you!

“Great things are done, by a series of small things brought together.” - Vincent Van Gogh

References

http://en.wikipedia.org http://www.thefreedictionary.com/nanoworld http://www.nanozone.org/why.htm http://www.nanotechplus.net/nanoimportant.html http://express.howstuffworks.com/express-nanotech1.htm http://www.rsc.org/Chemsoc/Chembytes/HotTopics/Nanotechnology/nanotechimportance.a

sp http://www.foresight.org/nano/ http://www.nanoword.net/pages/history.htm http://www.sciencedaily.com/releases/2004/04/040428062059.htm http://health.howstuffworks.com/medicine/modern/gold-nanotech.htm http://www.scitopics.com/Nanogold_chemistry.html http://ec.europa.eu/health/opinions2/en/nanotechnologies/l-3/5-nanoparticles-

consumer-products.htm http://www.understandingnano.com/nanotech-applications.html http://cnx.org/content/m14504/latest/