How The Nano “Revolution” Happened

Kasetsart UniversityNovember, 2004

0.000000001

But first, what is nano?

1 nm = 1 × 10-9 m500 nm Visible Light (blue-green)1 Å = 1 × 10-10 m typical chemical

bond (1.5 Å)1 Å = 0.1 nm

1.54 Å0.154 nm

C

C

CC H

0.109 nm

H

1.09 Å

Does the Language of Units Matter?

Body temperature 100oF 37oC = “hot”1 foot = about the size of your foot! No such

simple, physiological reference for the meter (about the length of your leg?)

1000 mL = a lot easier for chemists to imagine than 1 dm3

1 atm = a lot easier to imagine than 101,325 Pa

The discipline of Chemistry often loses the battle of language. The nano revolution is yet another such case, because the natural “unit” of Chemistry is the Angstrom.

More Syllables

Angstrom = 2 syllablesNanometer = 4 syllables

So….old people, who have learned that no one listens anyway, prefer Angstrom to Nanometers.

Anyway, something happens at ~1 nm

Technical Interface

Social Impact

Quantum vs. Classical

Molecular View vs. Materials View

Molecule vs. “device”

Learn fundamentals vs. Learn Toolbox

Chemists & Chemical Engineers vs. Materials Scientists & Engineers

Example: CdSeZnS quantum dots

http://smb.chem.ucla.edu/research/nc.htm

Absorption & emission of 5 different sizes

Dispersed in toluene. These particles have many advantages over conventional fluorophores—not easily bleached, broad excitation spectrum, narrow & tunable emission, long fluorescence lifetimes.

Gold particles made by alfalfa, a forage crop

http://www-ssrl.slac.stanford.edu/research/highlights_archive/alfalfa.htmlGardea-Torresdey UTEP

A Brief History of Nano

Richard P. Feynmanhttp://www.feynmanonline.com/The Feynman Lectures on Physics

“There is plenty of room at the bottom.”

December, 1959, exposition of just how much might be achieved by focusing on the enormous gap between the nano world and the big world.

•This talk was a social function—an after dinner talk.•Replication of machines, each smaller than parent.•Information on head of pin and in head of pin.

Who knows the word “pin”?

1/16”=1.5875 mm= 1,587,500 nm=15,875,000 Å

1/32”=0.79375 mm=793,750 nm=7,937,500 Å

Pin head volume: 1.6 × 1018 Å3

Age of universe in seconds: ~3 x 1017

Miniaturization at the dawn of the space age is not as we

now imagine.Miniaturization was on everybody’s mind,

following Sputnik – small guidance systems, radios, control systems.

“That’s nothing. That’s the most primitive, halting step in the direction I intend to discuss.”

“Why cannot we write the entire 24 volumes of the Encyclopedia Brittanica on the head of a pin?”

This requires the text to be reduced by 25,000 times.

Each letter then would then be several tens of atoms large.

“…there is no question that there is enough room on the head of a pin to put all of the Encyclopedia Britannica.”

Visual approach: simply shrink the text.

Coded approach: dots and dashes, e.g. let A -

Also: the pin has a finite thickness; we can use that,

too. Voxel = 3-D pixel125 atoms

All information in all the world’s 24 million books (in 1959) will now fit into the head of a pin.

A billion tiny lathes

Feynman raised the idea that a machine could make a replica of itself, only smaller.

Then, the smaller machine could make a replica of itself.

And so on and so on…Feynman allowed that such machines might

one day manipulate just small number of atoms, and he didn’t worry much about thermal vibration—the kT problem.

The Two Feynman Prizes

“And I want to offer another prize…of (a thousand dollars) to the first guy who makes an operating electric motor – a rotating electric motor which can be controlled from the outside and, not counting the lead-in wires, is only 1/64th inch cube.”

1/64th inch = 0.4 mm = 400 m = 400,000 nm

The first was for reducing information on a page by 25,000 times, so it could be read by an electron microscope.

William McClellan’s award-winning motor…but it broke no new ground. It is just a conventional motor, made very small using galvanometer wire and assembled under a microscope.

K. Eric Drexler, “author, theoretical researcher, and policy advocate focused on emerging technologies and their consequences for the future.” -- The Foresight Institute

http://www.foresight.org/FI/Drexler.html

About Drexler• Almost my age.• Spent part of his youth in Denver, my home

town.• Obviously, having a career of higher impact! • I do not know how much science he has

actually done. He clearly thinks about science a lot.

• Maybe compare to Leo Szilard of a previous generation? (Szilard thought about nuclear weapons and their social implications.)

Anyway, the point is…• Drexler was interested in space colonization during his

MIT years (1970’s).• Began to think of ways to make machines that

manipulate matter – e.g., why not a nanomachine that converts grass to meat to replace this “machine” in the “big world”?

• In the 1970’s the best manipulators of molecules were the biotech people, so why not imagine proteins—maybe synthetic—that would follow codes—maybe like DNA—to do what we want?

• Drexler’s ideas were independent of Feynman, whose 1959 banquet speech was, by that time, largely forgotten.

Proc. Natl. Acad. Sci. USA Vol. 78, No. 9, pp. 5275-5278, September 1981

Chemistry section

Molecular engineering: An approach to the development of general capabilities for molecular manipulation

KEY WORDS: molecular machinery/protein design/synthetic chemistry/computation/tissue characterization

K. Eric Drexler

Space Systems Laboratory, Massachusetts Institute of Technology,Cambridge, Massachusetts 02139

Communicated by Arthur Kantrowitz, June 4, 1981

ABSTRACT: Development of the ability to design protein molecules will open a path to the fabrication of devices to complex atomic specifications, thus sidestepping obstacles facing

conventional microtechnology . This path will involve construction of molecular machinery able to position reactive groups to atomic precision. It could lead to great advances in computational

devices and in the ability to manipulate biological materials. The existence of this path has implications for the present.

“it seems difficult to maintain that nonprotein machine components cannot be built and assembled”

Big world Function Bio/nano world

Struts, beams

Transmit force, hold positions

Microtubules, cellulose

Cables Transmit tension

Collagen, silk

Motors Convert energy to motion

Flagella

Containers Hold things Vesicles, cells

Programmed control

Store & read programs

Genetic system

Clinton/Gore

What did Feynman think of Drexler?

“That’s simple stuff. It’s obvious. Why doesn’t he work on something difficult?”

*according to author Ed Regis, Feynman was a guest at a Drexler party, and was asked what he thought by another guest, who was unaware that he was that Richard

Feynman.

US Government Studies1995It is unclear which fabrication method will best

succeed… Areas that are important…include:

• Macromolecular design and folding• Self-assembly methods• Catalysis• Dendrimers, fullerenes and other novel

structures• Bioenergetics, nanobatteries, and

ultrasound-driven chemistry• Semiconductoro-organic/biological interfaces• Miniaturization and massive parallelization of

(surface force microscopy)• Molecular modeling tools

1995• “Demonstration of assembly, control of

chemistry and practical component and integration are important.”

• Produce material parts at nanoscale• Process the parts into components• Order the components and interconnect• Control massive collection of miniature

parts and systems• Provide power

How to coordinate such an effort among NSF, NIH, DARPA, NIST, Industry?

Dangers

• Lethal and specific poisons• Potent drugs/new forms of drug

abuse• Uncontrollable viruses• Sabotage by miniature robotic

attackers• Competition with superior artificial

intelligence

2001 Report: A broader technology report, with a more realistic, limited approach with benefits in the short

term • Clothes that respond to weather, interface

with information systems, monitor health and deliver medicines, protect wounds.

• Personal identification & security.• Buildings and cars that adjust to weather. • Integration of chemical, fluidic, optical

and mechanical systems with biological functions and computer logic.

• Artificial tissue growth for heart, blood vessels.

• Functional materials—e.g., polypeptides.

2001 – broader impacts

• Accelerating pace of technology—lifelong learning. • Increasing interdisciplinarity. • Competition—e.g., with EU (in 1995, the concern

seemed to be Japan). • Reduced privacy.• Too much knowledge: if nanosensors of brain

function teach us how we form false memories, will we have to know the mental state of a witness in a murder trial?

• Nanorobots--”…it seems unlikely that macro-scale objects could be constructed using molecular manufacturing within the 2015 timeframe.”

Some Impressions of Nano

STM image of DNA

Nanowires from electrodeless reduction of Ag onto DNA. The wires get thicker with

each exposure to the AgNO3 solution.

We’re a long way from self-replicating, reducing machines.

Top-down, lithography,epitaxy, etc.

Bottom-up,chemical assembly

Should it win a Feynman Prize ?

IBM spelled out using 35 atoms of Xe

Another Classic Nanophoto from IBM

Nanotechnology viewpoints

• Nanoscience may viewed in many ways.

• Some people think it is all hype!• Some people think it distracts from

the fundamental studies that got us this far.

• Some people don’t care—just want a job!

My provisional viewpoint

• Some of Nano is definitely hype. • So what? Take the money and have fun!• Science has always oscillated between

opportunistic exploration and fundamental studies. That the pendulum has swung towards exploration and away from basics science is no cause for alarm.

• Students should still learn fundamentals so they can be ready for the next trend (and not make idiots of themselves during this trend cycle).

• The emergence of Nano probably is a symptom of the aging of Chemistry—or maybe Chemistry remaking itself.

I am still not sure!

Chemistry as we know it

Needs periodic table!

Many new Nano alphabets?

• Dendrimergenerations

• Fullerenes: C60, C70, etc. • Even silica particles of different

sizes???• Various nano-rods• DNA parts with complementary

“glue”ATGCTACG

We Hobbits can ride the great shoulders of the ents.

http://fan.theonering.net/middleearthtours/ents.html

While it is helpful to know as much as possible of the past, perhaps the immediate future belongs to visionaries who know how to put together capabilities.

This is a new approach. It seems to underlie much of nanotechnology—application of old facts, with rather less attention paid to fundamentals.

Treebeard

OriginsWe can thank

colloid chemists and polymer chemists, like these Nobel prize winners, for establishing some of the language and methods for studying material on the nanometer scale.

Often it has been macromolecular greatness that contributes to nanotech.

Ruska, Binnig, Rohrer

Onsager

Heeger, Shirakawa, McDiarmid

De Gennes

Svedberg

Flory

Debye

Staudinger

Rayleigh

Langmuir Merrifield

Confession and Caveat

I am a physically-inclined macromolecular scientist, not a nanotechnologist.

Already the nano field is very large, so even the most best nano expert would not be able to cover all of it.

Let’s just have fun with some of the nano possibilities.

Nano Centers

UCLA/UCSB: CNSI http://www.cnsi.ucla.edu/news.html

Institute for Nanosoldier Technologies

Rice CBM2

References

Nano, by E. Regis. Little, Brown & Co. Boston, 1995 (T174.7 R44)

Nanocosm, by W.I. Atkinson, Amacom, New York, 2003 (T174.7 A88)

The Global Technology Revolution, Bio/Nano/Materials Trends and their Synergies with Information Technology by 2015, prepared for the National Intelligence Council, by P. S. Anton, R. Silberglitt, J. Schneider, Rand Corporation, National Defense Research Institute, Santa Monica, 2001 (T173.8 A58)

The Potential of Nanotechnology for Molecular Manufacturing, by M. Nelson, C. Shipbaugh, Rand Corporation, Santa Monica, 1995 (T174.7 N45)