11-09 :: September 2011
nanotimes News in Brief
31
Inside the STM in the Sykes Laboratory. © Alonso Nichols, Tufts University
Photo of senior author Charles Sykes. © Alonso Nichols, Tufts University
molecule had carbon and hydrogen atoms radiating off to form what looked like two arms, with four carbons on one side and one on the other. These carbon chains were free to rotate around the sulfur- copper bond.
The team determined that by controlling the tem- perature of the molecule they could directly impact the rotation of the molecule. Temperatures around 5 Kelvin, or about minus 450° Fahrenheit (-268° C), proved to be the ideal to track the motor‘s motion. At this temperature, the Tufts researchers were able to track all of the rotations of the motor and analyze the data.
While there are foreseeable practical applications with this electric motor, breakthroughs would need to be made in the temperatures at which electric mo- lecular motors operate. The motor spins much faster at higher temperatures, making it difficult to measure and control the rotation of the motor.
“Once we have a better grasp on the temperatures necessary to make these motors function, there could be real-world application in some sensing and medi- cal devices which involve tiny pipes. Friction of the fluid against the pipe walls increases at these small scales, and covering the wall with motors could help drive fluids along,” said Sykes. “Coupling molecular motion with electrical signals could also create minia- ture gears in nanoscale electrical circuits; these gears could be used in miniature delay lines, which are used in devices like cell phones.”
Heather L. Tierney, Colin J. Murphy, April D. Jewell, Ashleigh E. Baber, Erin V. Iski, Harout Y. Khodaverdi- an, Allister F. McGuire, Nikolai Klebanov & E. Charles H. Sykes: Experimental demonstration of a single-molecule electric motor, In: Nature Nanotechnology AOP, Septem- ber 4, 2011, DOI:10.1038/NNANO.2011.142: http://dx.doi.org/10.1038/NNANO.2011.142