They may have a space-age feel to them, but aerogels got their start almost three-quarters of a century ago.
In
1931, Steven Kistler of the College of the Pacific in Stockton, Calif.,
took the first steps to prove that a theoretical “dry” gel contained a
continuous solid network of the same size and shape as its familiar
“wet” counterpart.
Kistler
first achieved success using a silica gel (aqueous sodium silicate) by
washing it with water, then exchanging the water for alcohol. By
converting the alcohol to a supercritical fluid and allowing it to
escape, he formed the first aerogel.
There
was a big buzz in the materials science community about Kistler’s
discovery and he left his academic post to manufacture aerogels for
Monsanto.
However, by the 1960s, new innovations led to a less expensive and less
costly alternative to the primitive aerogels; they were old news.
By
the early ‘80s, advancements in the production process and materials
put aerogels back on the radar screen. They could now be engineered and
designed with numerous applications—more than their past duties as
thickening/anti-caking agents in makeup and toothpaste.
Now
BASF,
Hoechst Corp
and agencies like Lawrence Livermore National Laboratory and NASA are
looking into aerogels’ potentialities. Silica aerogels, developed by
the Jet Propulsion Laboratory, have flown on Space Shuttle missions to
capture high-velocity cosmic dust particles.
Back To The Future
This new generation of aerogels holds great promise for a broad array of industrial and scientific uses.
Since
the material is fundamentally like solid smoke, it’s incredibly light
(about 95 percent air) yet stable and strong, with an impressive
resistance to heat transfer.
Think
lighter armored vests; stronger bumpers for motor vehicles; safer gas
tanks and safer storage for volatile materials; better tires; more
efficient insulated windows, refrigerators and thermoses; lighter and
more efficient frames of aircraft and trains.
Because
the process itself is in broad use, it’s the companies that begin to
incorporate these far-sighted processes into their current
manufacturing and design schedules that will find themselves moving
ahead of the competition.
A New Twist
The
newest iteration of the aerogel revolution is what’s termed nanofoams.
Even once through the nanofoam rabbit hole, there remain a variety of
definitions. A new process developed in Australia came about
accidentally while scientists were attempting to make fullerenes.
After
blasting a laser at graphite in an argon gas chamber, scientists
noticed that around 10,000 degrees C, when the carbon atoms separated
out of the graphite, the separate carbon atoms settled into clusters as
they cooled.
This
nanofoam has several very bizarre magnetic properties. But it will be
some time before any real implications can be gleaned from this foam;
the foam degraded very quickly and was a byproduct of another process,
so the scientists weren’t prepared to do much experimentation.
Its
most exciting potential lies in the material’s semiconducting and
magnetic properties. Should future work create a stable, magnetic
semiconductor that can operate at room temperature from the nanofoam,
another door will open that would revolutionize computing as we know it.
Spintronics
Basically,
spintronics is a theoretical field of computing. It posits that if you
could develop a computer that operated off magnetism (the spin of
electrons) rather than electricity, you could actually create quantum
computers that would be incredibly powerful, yet stunningly power
efficient.
Already, major players like
IBM,
Intel,
Sun Microsystems and
Hewlett-Packard
are developing the next wave of magnetic random-access memory (MRAM).
Last-generation, spintronic-based MRAM is incorporated into many
notebook computer hard drives. But this next-generation step has the
potential to be earth shattering.
Bear
in mind, spintronics is still in its toddler years. The theoretical
potentialities have yet to be fully explored, much less any blessed
accidents that may occur along the way. But this is more than some
pie-in-the-sky hope or snake oil hype. It’s tangible and big.
If
you’re interested in getting a firmer grip on this field, its current
players and its implications for the future of computing, the best
places to start are the links below:
The Center for Spintronics and Quantum Computation:
http://www.csqc.ucsb.edu/
New Scientist.com—the latest on spintronic switching:
http://www.newscientist.com/article.ns?id=mg18424742.400
Scientific American.com--2002 in-depth article on spintronics:
http://www.sciam.com/article.cfm?articleID=0007A735-759A-1CDD-B4A8809EC588EEDF
NVE Corporation—an MRAM builder
http://www.nve.com/
GS Early
Gregg Early is vice-president of
KCI Communications and
executive editor of the company’s flagship publication, Personal Finance.
Over
the past decade, he has helped build the newsletter’s reputation as a trusted
source for penetrating market analysis and investment advice that subscribers
can take to the bank. He also oversees the editorial department’s other
award-winning publications.
But Gregg’s responsibilities
and interests are not purely administrative. Always forward-looking, he found
his niche reporting on the frontiers of technology: high-temperature
superconducting, alternative energy, intelligence infrastructure, as well as
advances in the nanotech and biotech sectors. For those willing to follow him
back to the future, he pens The Real
Nanotech Investor, a financial advisory that focuses on how individual
investors can capitalize on innovations in nanotech and disruptive
technologies. Gregg’s free e-zine, Nanotech
Investing News, keeps readers updated on the latest advances and
developments in these nascent sectors and, more importantly, the opportunities
therein.
Prior to joining KCI, Gregg
honed his journalistic chops reporting on a variety of topics including
finance, health care and education. He is also a respected gastronome and chef
as well as a published poet and playwright. He’s a graduate of James Madison
University.
View all articles by GS Early