A nano ‘car’ with molecular 4-wheel drive

November 11, 2011

Molecular "car" on a copper surface with four electrically driven wheels (credit: Empa)

STM provides electrons (blue) to drive car-like molecules with four motorized ‘wheels’ (purple) across a surface (credit: Paul S. Weiss/Nature)

Scientists at the University of Groningen and Empa have created a 4 nanometer-long artificial nanoscale transport system (“car”) by synthesizing a molecule with four rotating motor units (“wheels”).

The “car” is refueled with electricity after every half revolution of the wheels. To do that, they sublimated the molecule onto a copper surface and positioned an scanning tunneling microscope (STM) tip over it, then applied a small voltage to make electrons “tunnel” through the molecule, triggering reversible structural changes in each of the four motor units (“wheel”).

Next, they plan to develop molecules that can be driven by light, perhaps in the form of UV lasers.

Ref.: Tibor Kudernac, et al., Electrically driven directional motion of a four-wheeled molecule on a metal surface, Nature, 2011; 479 (7372): 208 [DOI: 10.1038/nature10587]