Researchers at Rice university for the first time ever have created "Nanocar" from a single molecule with a chassis, axles and four buckyballs for
wheels. They used STM's to verify the rolling motion.
www.betterhumans.com...
"The synthesis and testing of nanocars and other molecular machines is providing critical insight in our investigations of bottom-up molecular
manufacturing," says James M. Tour, one of two lead researchers on the project. "We'd eventually like to move objects and do work in a controlled
fashion on the molecular scale, and these vehicles are great test beds for that. They're helping us learn the ground rules."
According to this News Release ...
The nanocar consists of a chassis and axles made of well-defined organic groups with pivoting suspension and freely rotating axles. The wheels are
buckyballs, spheres of pure carbon containing 60 atoms apiece. The entire car measures just 3-4 nanometers across, making it slightly wider than a
strand of DNA. A human hair, by comparison, is about 80,000 nanometers in diameter…
"It's fairly easy to build nanoscale objects that slide around on a surface," Kelly said. "Proving that we were rolling—not slipping and
sliding—was one of the most difficult parts of this project."
To do that, Kelly and graduate student Andrew Osgood measured the movement of the nanocars across a gold surface. At room temperature, strong
electrical bonds hold the buckyball wheels tightly against the gold, but heating to about 200 degrees Celsius frees them to roll. To prove that the
cars were rolling rather than sliding, Kelly and Osgood took STM images every minute and watched the cars progress. Because nanocars' axles are
slightly longer than the wheelbase—the distance between axles—they could determine the way the cars were oriented and whether they moved
perpendicular to the axles.
In addition, Kelly's team found a way to grab the cars with an STM probe tip and pull them. Tests showed it was easier to drag the cars in the
direction of wheel rotation than it was to pull them sideways.
Synthesis of the nanocars also produced major challenges. Tour's research group spent almost eight years perfecting the techniques used to make
them. Much of the delay involved finding a way to attach the buckyball wheels without destroying the rest of the car. Palladium was used as a catalyst
in the formation of the axle and chassis, and buckyballs had a tendency to shut down the palladium reactions, so finding the right method to attach
the wheels involved a good bit of trial and error.
This is a HUGE step towards Drexlerian Molecular Manufacturing, in a little under 10 years we went from spelling out I.B.M. in Xenon atoms to this! We
really need to start discussion the ethical, societal and technological implications of this right now as it's clearly closer then anyone suspects.
Allot of obstacles are still there to be dealt with but if we continue at this pace those obstacles could become moot very soon indeed.
The nanocar is reported in the journal
Nano Letters
[edit on 24-10-2005 by sardion2000]
It's just as cool as the 
