The Soot That Could Change the World
by Ivan Amato
This past Valentine's Day, a year-old Houston startup called Carbon Nanotechnologies Inc., or CNI, began FedExing jelly-jar-sized containers of a high-tech soot so coveted that buyers have been willing to plunk down $500 a gram for the stuff. That's $14,000 per ounce, far more than the price of gold. Although this jet-black material resembles what you'd wipe up from your fireplace, its champions talk as if it were the next steel or silicon. "This product will change the world," says Sylvain Hoebanx, president of Nanoledge in Montpellier, France, where he and his colleagues expect to spearhead his country's bid to capitalize on the new material.
Like their alchemist predecessors, the founders of CNI, Nanoledge, and other companies that are sprouting like crocuses in early spring know that appearances deceive. If you were to look closely enough at this soot to see its individual molecules, you would shake your head in disbelief. Before your eyes would be long cylinders of what appears to be molecular-scale chicken wire capped on either end by halves of soccer balls. They're known as carbon nanotubes. They are also called buckytubes, because of their resemblance to the geodesic structures designed by the 20th-century American engineer Buckminster Fuller. To any chemist's eye, they're drop-dead gorgeous.
Even more appealing are nanotubes' potential uses, says Rice University chemist Richard E. Smalley, a Nobel laureate and CNI co-founder. As he puts it, "They are expected to produce fibers 100 times stronger than steel at only one-sixth the weight--almost certainly the strongest fibers that will ever be made out of anything." In a visionary moment, Smalley talks of nanotubes braided into a cable that could support an elevator linking the earth's surface with a geostationary space platform 22,000 miles above the equator.
Unmatched strength is just one amazing property of these tiny structures. Researchers have found that buckytubes conduct electricity as well as copper does. They also channel heat at least as well as the world's best heat conductor--diamond. What's more, when a nanotube's chicken-wire structure twists around like the stripes of a barber pole, it behaves like a semiconductor. This capability boosts hopes for an era of transistors, wires, and other electronic devices thousands of times smaller than those in today's chips. In such an era, nanotube enthusiasts say, storage devices that fit in a shirt pocket could hold the contents of the Library of Congress--a point made by former President Clinton in his 2000 State of the Union address.
As Clinton was making his remarks, buckytubes were emerging from a decade-long phase of basic lab studies into the early stages of an entrepreneurial product-development derby. Several trends have been helping this transition along:
--Increasing amounts of government and corporate money are nourishing nanotechnology, the R&D movement that includes nanotubes. The biggest sources are the federal government's National Nanotechnology Initiative, which has $422 million in funds this year, and Mitsubishi Corp.'s new $100 million venture fund to support the development of all-carbon materials.
--Dramatic price breaks have taken away some of the hesitancy of would-be product developers. For example, CNI's $500-a-gram price is down from the $2,000 charged by its noncommercial precursor. Other sources offer nanotube materials for much less, and prices are expected to keep falling steeply as production volumes climb.
--Many companies, including South Korea's Samsung, America's Motorola, and Japan's Ise Electronics, are working on what they bet will be the first killer applications of buckytubes: electronic displays. Carbon-based screens scarcely thicker than this issue of FORTUNE could render higher-resolution images than today's cathode-ray-tube (CRT) and flat-panel displays while using less power. Also in development is a new generation of giant, lower-cost illuminated signs like those in urban crossroads such as Times Square and the Ginza.
The genesis of today's buckytube excitement was a 1985 discovery by three men: Harold Kroto of the University of Sussex in England, Rick Smalley, and his Rice colleague Robert Curl. In the laboratory they created soccer-ball-shaped molecules called C60, which became known also as buckyballs and buckminsterfullerene. Made of 60 carbon atoms arranged in a soccer-ball tiling of pentagons and hexagons, C60 represented a new structural form of carbon, the same element as diamond and graphite and the one most central to life. In Kroto's words, "The structure is too beautiful to not exist."
But there was a problem. The initial lab technique produced vanishingly tiny quantities of buckyballs. The situation improved in 1990, when scientists in Heidelberg, Germany, and in Tucson published a paper in Nature describing how to make larger quantities. Just send high-voltage electrical sparks between pairs of closely spaced graphite rods spiced with metal-based catalysts, and you could create a rarefied rain of C60 and related all-carbon stuff. Soon several laboratories were making enough fullerene material--as it is generically known--to sell. A buckyball heyday seemed in the offing. To date, though, buckyball products remain in the development stage.
Then, in 1991, something unexpected happened at the NEC company in Tokyo. While using an electron microscope to examine the fullerene soot he had made, researcher Sumio Iijima observed something that would steal the thunder from buckyballs: some of the tiniest tubes of carbon anyone had ever seen. Tens of thousands of times thinner than a human hair, these structures turned out to be like a retracted antenna, a nesting of tubes within tubes. They would become known as multiwall carbon nanotubes, to distinguish them from the simplest of all nanotubes, the one-atom-thick structures referred to as single-wall nanotubes. Later that year, at a technical meeting in Philadelphia, research- ers shared their early calculations about just how strong, conductive, and otherwise talented carbon nanotubes were likely to be.
At the same meeting, Smalley recalls, materials scientist Mildred Dresselhaus of MIT coined the term "buckytube." She also told him that he almost certainly had been making nanotubes in his lab without knowing it. That's when he and many other buckyball researchers jumped ship to embrace buckytubes. Smalley decided to concentrate on the single-wall variety, since it would be easier to study, measure confidently, and understand than the more variable multiwall type. Single-wall nanotubes are also smaller--a mere nanometer (a billionth of a meter) or so in diameter and up to a micron (a millionth of a meter) or so long. Nanotubes of this type sufficient to span the 250,000 miles between the earth and the moon at perigee, Smalley and a colleague once calculated, could be loosely rolled into a ball the size of a poppy seed.
The challenge was to produce meaningful quantities of nanotubes, whether single- or multi-wall. For several years, what researchers could make was often a mixture of both types, along with annoying impurities about as interesting as fireplace soot. But in 1995, Smalley's group, for one, found it could generate nearly pure nanotube dust using a so-called laser oven. By laser-blasting targets of graphite laced with metallic catalysts that served as tiny molecule-building platforms, the researchers on a good day could create as much as a gram of nearly pure single-wall nanotubes.
The growing demand for buckytubes prompted the creation of Tubes@Rice, a university-sponsored enterprise. In September 1998 the first shipments of gram- and subgram-sized buckytube samples started moving from Houston to points around the world at a standard price of $2,000 per gram. A handful of other small suppliers began making various kinds of buckytubes, using a variety of methods. Still sorely lacking was a process that could be scaled up to make pounds, if not tons, of buckytubes.
Pasha Nikolaev, then one of Smalley's graduate students, made an important leap in 1998. Pasha, as he is most often known, persuaded Smalley to let him try feeding carbon monoxide gas into the laser oven under higher pressure than anyone had tried before. When Pasha examined the oven's quartz tube within which the buckytubes normally form, he noticed a black film on one end that peeled away like skin. "He went downstairs to the electron microscope and saw he had nanotubes," and lots of them, recalls CNI-co-founder Ken Smith.
From Pasha's hunch has evolved the so-called high-pressure carbon monoxide process, or HipCO. Smalley says it has tremendous potential because it produces 98% pure single-wall nanotubes and can be scaled up to make more of them at a lower cost. With a viable process in hand, Smalley was able to win over Bob Gower, a Ph.D. chemist with a track record in turning money-losing petrochemical companies in Texas into healthy billion-dollar commercial engines. Gower provided his managerial expertise and over $1.3 million dollars of his own money to rev CNI up to speed.
CNI, having made its first shipments this past February, is already bursting out of its academic digs. Gower helped secure laboratory and pilot-plant space at a facility run by the industrial engineering and construction firm Kellogg Brown & Root. In April the company announced that two other Houston technology investors had kicked in $15 million in venture money. Within a few years, says HipCO co-developer and CNI co-founder Dan Colbert, the company ought to have learned enough from a pilot plant to build a full-sized factory with annual buckytube production measured in tons.
Already forming is what appears to be a buckytube technology chain extending from raw-material suppliers to buckytube-based product designers. On the supply end are a handful of competitors whose prices vary from CNI's $500 a gram all the way down to several dollars a gram for unpurified multiwall nanotubes. Because the quality, purity, and exact form of buckytubes vary, it's tricky to make meaningful price comparisons.
For example, CNI is the only company that makes single-wall nanotubes with its patented HipCO process. Others, such as MER, an advanced-materials firm in Tucson, make multiwall nanotubes using techniques such as arc-discharge systems, which rely on high-voltage sparks to zap the carbon in graphite electrodes into fullerenes. Still others, including Nanolab, a startup in Watertown, Mass., make nanotubes via chemical-vapor deposition, in which a carbon-bearing gas like acetylene is leaked into a chamber where heat breaks up the gas molecules. This liberates carbon atoms, which reassemble into buckytubes.
Last summer, says MER President Raouf O. Loutfy, the seed was planted for a buckytube pipeline of unprecedented size. That's when his company joined forces with Japan's Mitsubishi Corp. and Research Corp. Technologies, a technology development company in Tucson, to form Fullerene International Corp. As part of the venture, MER built a large arc-discharge reactor at Osaka's Hongo Chemical Co., where, Loutfy says, engineers have already ramped multiwall nanotube production up to a kilogram per day or more. At full capacity, the reactor is designed to produce 30 kilograms per day.
According to the newsletter Japan New Materials Alert, the Japanese government's National Institute of Materials and Chemical Research is working with chemical giant Showa Denko of Tokyo on an even bigger nanotube effort. These partners have built a chemical-vapor-deposition reactor designed to produce hundreds of kilograms of nanotubes a day, says Loutfy, who visited Japanese nanotube researchers last winter. Inside the reactor, catalyst particles and a carbon-bearing feed gas interact at temperatures over 1,000[degrees] C. to yield nanotubes. Material from this government-supported reactor, Loutfy says, is being given away to the country's high-tech companies in hopes of stimulating product development.
With so many processes producing a variety of nanotubes and everybody trying to patent whatever seems valuable, the nascent industry appears to be headed toward an intellectual-property war. The potential stakes are huge. CNI projects that as buckytube prices tumble, more and more of a wide-ranging set of markets totaling $100 billion a year will open up. Get the price of nanotubes down to $15,000 a pound, or about $33 a gram, the company estimates, and a yearly supply of one ton would be able to support the manufacture of several billion dollars' worth of flat-panel displays for PCs and television sets. Knock down the price to about $10,000, and buckytubes become ingredients for making stealthy, radar-absorbing aircraft skin and novel microwave antennas.
As prices go lower, CNI figures, nanotubes would become far more pervasive. At $200 a pound, they could find everyday use as additives to plastics to create lightweight materials for shielding laptop computers, cell phones, pagers, and other small, portable electronic devices from electromagnetic interference. At that price buckytubes would also begin making sense for use in batteries. Make the stuff as cheap as wood, and you could start making fabrics, beams, and large structural members. This would lead to lighter-weight power-transmission wires, cars, aircraft, spacecraft--maybe even those elevator cables to geostationary satellites.
It will take more than cheap and abundant supplies to usher in the nanotube age. One of the most far-reaching applications--molecular electronic chips and devices hundreds or thousands of times smaller than today's microcircuitry--wouldn't require huge quantities of buckytubes at all. However, it would take the ability to chemically modify, manipulate, and arrange a material that's extremely difficult to work with. The goal is a long way off, but researchers are taking steps toward it. In a recent issue of Science, for example, researchers at IBM reported that they had succeeded in building tiny electronic switches made with carbon nanotubes.
The quest to develop know-how for transforming nanotubes into products has become a cottage industry, mostly populated by university scientists. Cynthia Kuper, a recent alumna of Rick Smalley's lab, is as gleamy-eyed about the buckytube future as you might expect of a 28-year-old who is president of one of the latest startups, Versilant Nanotechnologies in Philadelphia. Operating initially on her own money and a modest Small Business Innovation Research grant from NASA, she says Versilant will buy raw nanotubes from suppliers and process them into aligned arrangements, fabrics, or, in her words, "things you can see, touch, feel, and buy."
In the raw, Kuper points out, buckytubes come out in tangles, often referred to as "ropes." These aren't good for much; researchers are just now developing ways to process the stuff into more useful forms. For example, Smalley's group relies on magnetic fields to align buckytubes like stacks of molecular-scale logs. Others have used liquid flows, electric fields, and other means to arrange buckytubes into sheets and even fine molecular-scale grids potentially suitable for ultradense data storage.
The image that Kuper floats for illustrating how amazing and versatile buckytube products could be is a military one: "Make a jacket for a soldier out of a single piece of fabric made only of single-wall nanotubes. The only things that vary in this fabric are the density of the tubes, the way they are aligned, and their doping, which controls their electronic properties. If you can integrate that into a fabric, it will have three-dimensional circuitry with computing power like nothing we have ever seen. It will also be a ballistic shield to stop bullets and a portable power supply--all in one material."
Even as fullerene visions like Kuper's proliferate, and as supplies of buckytubes go up and prices go down, their appeal increases for another surprising reason. Call it molecular mystique. Remarkably, the more ball-like fullerenes have been found in ancient rocks and in detritus from meteorite impacts. "They're also made in every candle flame and in forest fires," says Smalley, whose initial scientific passion has evolved into something more. "I get the feeling," he goes on, "that something incredible is unfolding, and that we have only seen a little piece of it so far.... It's been a religious experience to see this happen."
There was a religious connection of sorts for one financial supporter's entry into the most likely first killer app in the buckytube arena--the $40 billion flat-panel-display industry. It began after services one Sunday last September at the Trinity Episcopal Church in Stamford, Conn. That's when Andrew Hanson, an angel investor, had a discussion with fellow churchgoer Thomas Abraham, head of the advanced materials group at Business Communications Corp., a consulting firm in nearby Norwalk. As a consequence, by the end of the year Hanson had put down a big chunk of change, but not in the offering plate. "Six figures is the right ballpark," he says.
Abraham told Hanson about his company's new report on carbon nanotubes, which was released last November and sells for $3,995 a copy. Within months Hanson had taken the report's author, Sam Brauer, to lunch, learned what he could about nanotubes, and sent his check to Nanolab, the Watertown, Mass., startup. There, chemical engineer and company president David Carnahan grows, in his words, "grass fields of nanotubes on substrates," which the company sells to others trying to develop computer displays, batteries, or fuel cells.
If Nanolab grows as Hanson and Carnahan hope it will, within a few years it will become a premier player in the business of making computer screens. A new generation of the flat-panel type, known as carbon nanotube field-effect displays, or CNT-FEDs, is the first bigtime candidate for nanotube applications. The hope is that TV screens and those monster monitors on millions of desktop computers worldwide, which are TV-like CRTs, can be squashed into thin, widely affordable nanotube display panes. Compared with CRTs, and perhaps even with the liquid-crystal displays that are standard in today's laptops, nanotube displays could produce crisper images while using less power and could ultimately be cheaper to make.
"My initial take on the field was one of skepticism, but when I got into it, I saw things," says Brauer, author of Business Communications' nanotube report. One of the things he saw was a demo of a palm-sized CNT-FED made with billions of carbon nanotubes, each serving as a tiny electron gun whose diminutive bullets stimulate the color-emitting phosphors painted on the inside surfaces of the display's screen. The demo screen, made by a research team led by Jong Min Kim at Samsung's Advanced Institute of Technology in Suwon, South Korea, was unveiled in April 1999 in Dubrovnik, Croatia, at the Society for Information Display's annual conference. By year-end, the team was showing off a nine-inch version. Last May and December, it demonstrated 15-inch CNT-FED displays.
Although observers say that none of these is good enough or cheap enough yet to compete with the liquid-crystal or plasma flat panels currently in use, they have made Samsung the company to beat. "This year the mission of our team is to develop the key technologies using small seven-inch screens for technological confirmation before moving to larger ones," says Naesung Lee, Samsung's CNT-FED project manager. He says his company is targeting the 20- to 40-inch TV market, for which neither liquid crystal nor any other emerging display technology has secured a dominant position. If development continues as planned, Lee expects Samsung to launch CNT-FEDs in as little as three years.
Motorola, also in the CNT-FED fray, won't reveal much about what it is working on. "We have demonstrators, but we haven't shown them publicly," says researcher Ken Dean. Meanwhile, collaborating researchers at Japan's Mie University and Ise Electronics, a subsidiary of Noritake Co., have been showing off their own carbon-nanotube-based display prototypes. Rather than steering initially toward the TV and monitor market, Ise aims to make enormous electronic billboards, like those that illuminate Times Square, far more affordable.
Furthest along in the development pipeline is a cylindrical lighting element roughly an inch in diameter that resembles an old radio vacuum tube. Inside each element is a cathode made with a forest of nanotubes like those Nanolab makes. When voltage is applied, electrons stream from the nanotubes toward a phosphor-coated aluminum membrane, sending out bright light from the element's glass enclosure.
"These elements can be used as pixels in giant outdoor displays and light sources for liquid-crystal-display projectors," says Yahachi Saito, a professor of electrical and electronic engineering at Mie University, where he works on the project. Notes Saito: "In the field of large-scale displays, reduction of power consumption is of vital importance." Of the various display technologies now under consideration, he adds, carbon-nanotube-based displays are expected to require the least power.
Somewhat further in the future are other potential billion-dollar markets for buckytubes. Nanolab and CNI, among others, see many possibilities. Batteries made with carbon nanotubes, for example, ought to achieve much higher "energy densities" than today's batteries by packing charged particles more efficiently than the graphite anodes of lithium batteries. The payoff would be a battery that lasts twice as long as today's or weighs half as much.
Buckytubes could also be used to make "supercapacitors" for cars. Every time a driver steps on the brakes, cars waste tremendous amounts of mechanical energy as heat. But the enormous amount of surface area harbored by even tiny amounts of nanotubes presents an intriguing opportunity to convert that energy into electrical power. "If you want to capture that energy, you need something that can absorb it all at once," says Nanolab's Carnahan. The car's brakes would not be lined with nanotubes, but the energy released by stopping could be converted to electricity in the engine. The electrical charges thus created need to hang out somewhere, and surfaces are great places for that. A capacitor packed with buckytubes could capture far more of this energy than present "regenerative" braking systems.
This same surface-area trait makes carbon nanotubes an excellent candidate material for fuel cells. These convert chemical fuel directly and cleanly into electricity via catalyzed chemical reactions, and a layer of buckytubes could store that electricity more efficiently. (For more on fuel cells, see the following article.) In the back of everyone's mind, too, is the long-term hope that enough buckytubes will become available for making new reinforced polymer composites for spacecraft, planes, and other vehicles. Moreover, if chemists become adept at modifying them so that they can become the basis of molecular electronic chips, a nanotube-based microprocessor would make today's Pentium IV circuitry seem as oversized as arrays of vacuum tubes compared with today's chips.
For now, the biggest market for carbon nanotubes is still, as it always has been, in raw material for the R&D community. In his report, Brauer estimates that carbon nanotube sales reached just $1.4 million last year. He nevertheless predicts that sales of nanotubes and the products they make possible will grow to about $400 million by 2004, or perhaps to $1 billion by that time if the cost of nanotubes dips as substantially as its champions promise. An age of carbon nanotubes may not be right around the corner. But just about everybody working with them believes these beautiful molecules are looking more and more like the basis of some very good stuff indeed.
Source: Fortune Magazine
Monday, June 25, 2001
Author: Ivan Amato