This year's model isn't your father's nanocar. It runs cool.
The drivers of Rice University's nanocars were surprised to find modified versions of their creation have the ability to roll at room temperature. While practical applications for the tiny machines may be years away, the breakthrough suggests they'll be easier to adapt to a wider range of uses than the originals, which had to be heated to 200 degrees Celsius before they could move across a surface.
The nanocar was a sensation when introduced in 2005 by the lab of James Tour, Rice's Chao Professor of Chemistry and a professor of mechanical engineering and materials science and computer science.
Tour's original single-molecule car had buckyball wheels and flexible axles, and it served as a proof-of-concept for the manufacture of machines at the nanoscale. A light-activated paddlewheel motor was later attached to propel it, and the wheels were changed from buckyballs to carboranes. These were easier to synthesize and permitted the motor to move, because the buckyball wheels trapped the light energy that served as fuel before the motor could turn. Since then, nanotrucks, nanobackhoes and other models have been added to the Rice showroom.
A large-scale representation of the nanocar made its public debut in Houston's famous Art Car Parade last year.
Rice's Stephan Link, an assistant professor of chemistry who specializes in plasmonics, took the wheel for a new series of experiments that built upon Tour's pioneering work. Link's primary achievement was using single-molecule fluorescence imaging to track the tiny vehicles, as opposed to the scanning tunneling microscopy (STM) used in earlier experiments. STM imaging can capture matter at an atomic scale, but the technique requires the target to be on a conductive substrate. Not so with fluorescent imaging.
A paper on the new research published this month in ACS Nano was authored by Link; Tour; Anat
|Contact: David Ruth|