Defining Nanotechnology  NANO  refers to objects on the nanometer scale (most say anything less than 100 nm)  TECHNOLOGY  the current state of our knowledge of how to combine resources to produce desired products, to solve problems, fulfill needs, or satisfy wants (Wikipedia)

Nano-related Events  1959: Richard Feynman gives his famous paper on nanotechnology There’s Plenty of Room at the Bottom on December 29th at the annual meeting of the American Physical Society at the California Institute of Technology (Caltech).  1985: Robert Curl, Harold Kroto and Richard Smalley make the completely unexpected discovery that the element carbon can also exist in the form of very stable spheres. They termed these new carbon balls fullerenes or “buckyballs”. Curl, Kroto and Smalley subsequently win the 1996 Nobel Prize for Chemistry.  1986: Eric Drexler publishes Engines of Creation : The Coming Era of Nanotechnology, in which he examines the enormous implications of nanotechnology for medicine, the economy, and the environment.  2001: The Clinton administration raises nanoscale science and technology to the level of a federal initiative, officially referring to it as the National Nanotechnology Initiative (NNI).

Forms of Carbon (Allotropes) ~0.70 nm graphite “buckyball” “buckytube” diamond

Growing Nanotubes Forest of nanotubes Single-walled nanotube (SWNT)

Nanoparticles are not new…  There are many examples of the use of nanoparticles in history  The Lycurgus Cup (Roman 4 th century AD) derives its unusual properties from gold/silver nanoparticles embedded in glass  Carbon nanoparticles (in the form of soot) have been used to reinforce tires for over 100 years

How Small Can You Get?  A human hair is about 100 microns (micrometers) wide  One micron is about times the thickness of a dime  Current microchip transistors are about two microns wide  The wires that connect the transistors are less than a micron wide  If vacuum tubes were used in place of the transistors on a microchip the chip would be the size of a city block!

Population Densities 376 million transistors per chip (Pentium D 940 – “dual core”) 100 billion+? components / wafer 6 billion people / world

The Shrinking Transistor

Micromachines (MEMS)  Current applications  inertial sensors (e.g., in air bags)  medical devices  memory and mass storage  micro-mirrors for digital projection (DLP)

A “Nano” Guitar!

How Can We See Small Things?  Atomic Force Microscopy cadmium selenide silicon

Refrigerator Magnet Imaging pull probe strip probe sample

What is the best representation? (a)(b)(c)

Imaging Atoms STEM image of a silicon crystal in the [112] orientation reveals pairs of atom columns in which the intrapair separation is 0.78 Å. Scanning-Tunneling Electron Microscopy (STEM) image shows individual platinum atoms (bright blobs) on an alumina support, with Pt 3 clusters circled.

Manipulating Atoms A 40-nanometer-wide NIST logo made with cobalt atoms on a copper surface. The ripples in the background are made by electrons, which create a fluid-like layer at the copper surface. Each atom on the surface acts like a pebble dropped in a pond. Joseph Stroscio; Robert Celotta / NIST A single cobalt atom

Nanotechnology Products  Electronics  processors (current production Pentium D chips use 65 nm technology)  memory chips and storage devices  displays based on OLED (organic light- emitting diode) technology are brighter, use less power, and have a wider viewing angle than conventional diplays

Nanocrystals  “Quantum dots” are nm sized crystals that have unique optical properties. They absorb ultraviolet light and re-emit light that depends on their size (see above figure)  Qdot ® nanocrystals are marketed by Invitrogen TM as very specific fluorescent stains that can be used to track activity in live cells smaller

Nanocrystals  NUCRYST Pharmaceuticals develops and manufactures medical products that fight infection and inflammation based on nanocrystalline silver technology.  Smith & Nephew's Acticoat™ antimicrobial barrier dressings (based on NUCRYST technology) rapidly kill a broad spectrum of bacteria in as little as 30 minutes

Gold nanoparticles in biochemistry and medicine

Nanoparticles and nanofibers  Stain-repellent Eddie Bauer Nano-Care TM khakis, uses a process that coats each fiber of fabric with “nano-whiskers”, helping the fabric to repel liquids.  Sunscreens are utilizing nanoparticles that are extremely effective at absorbing light, especially in the ultra-violet (UV) range. Due to the particle size, they spread more easily, cover better

Nanocomposites  Composite refers to a combination of two types of materials (fiberglass = plastic resin + glass fibers).  GM and Toyota use plastic nanocomposite materials for “step assists” and bumpers. They are stronger, more scratch resistant and lighter than older materials.  Wilson has created nanocomposite-based tennis rackets and golf clubs

Nanotubes  Many companies are trying to perfect “field effect displays” that are based on emission from individual nanotubes  Similar to CRT, but each nanotube serves as an individual electron gun  Uses less power than LCD or plasma, but picture similar in quality to CRT  May see FED-TVs on shelves in 2006

Nanocatalysts  Catalysts enhance the rate of chemical reactions, making chemical conversion or manufacturing more efficient  China's largest coal company (Shenhua Group) has licensed technology from Hydrocarbon Technologies that will enable it to liquify coal and turn it into gas. The process uses a gel-based nanoscale catalyst.

Nanofilters  Argonide Nanomaterials, an Orlando based manufacturer of nanoparticles and nanofiltration products, makes a filter that is capable of filtering the smallest of particles.  The performance is due to it’s nano size alumina fiber, which attracts and retains sub-micron and nanosize particles. This disposable filter retains % of viruses at water flow rates several hundred times greater than virus-rated ultra porous membranes.