Smallest electric engine could power future nanomachines

LONDON - Scientists at the Delft University of Technology in the Netherlands have designed a blueprint for the smallest electric engine ever that could eventually drive tiny conveyor belts or pumps in future nanomachines.

The motor’s rotor is a long, coal-derived molecule called anthracene. It possesses what is known as a dipole moment - its negatively charged electrons tend to congregate at one end of the molecule, making the other end positively charged.

Tiny motors that are powered by light or magnetic fields have already been developed, but electricity carries advantages, said team member Jos Seldenthuis, reports New Scientist.

“Even the most narrowly focused beam of light is still a few hundred times larger than a single molecule,” he said, making it difficult to control individual motors. An electric current can be directly applied to single motors for applications requiring the operation of several independent devices.

Electricity also gives the nanotechnologists an easy way to detect that the anthracene rotor is actually turning, which can be difficult at such tiny scales. This is because the electrical conductivity of the motor, as measured by the two electrodes on either side of it, should change in a regular way as the rotor turns.

However, James Tour, a materials scientist at Rice University in Houston, Texas, warned that such machines are much easier to design than to build.

To which Seldenthuis said, “In collaboration with other groups, we are now working hard on the experimental realisation of this concept. Individual aspects of the design have already been verified experimentally.”

The study is published in ACS Nano. (ANI)