Nanomotor movement can now be controlled remotely, say US researchers. 

Joseph Wang at the University of California San Diego and colleagues have, for the first time, demonstrated electrochemical control of a fuel-driven nanomotor. Wang and his team pioneered a new generation of fuel-driven catalytic nanomotors and now they can also control their speed and starting and stopping motion. 

Nanomotors are tiny molecular devices capable of converting energy into movement. Wang developed a nanomotor where the on/off mechanism is controlled by a gold electrode placed near the motor applying different potentials. The potential in the microelectrode triggers electrolytic reactions of the fuel constituents. Wang explains that 'a positive or negative potential in the electrode leads to generation or consumption of oxygen, respectively, which leads to stoppage or acceleration of motion, respectively.' By controlling the exact negative potential, the oxygen level is controlled and hence the motor speed. 

Henry Hess, an expert on engineering applications of nanoscale motors at the University of Florida, US, highlights that 'this principle might ultimately lead to networks of electrodes which guide the speed and direction of catalytic nanomotors like radio beacons guide airplanes along their path.' 

Wang is excited by the possibilities that have opened up by this work. The on-demand triggering of motion and the control of speed is 'a first step towards the challenging design of functional nanomachines,' he says. The team's future work will include trying to achieve faster on/off activation and more complex movement patterns. 

Roxane Owen 

Enjoy this story? Spread the word using the 'tools' menu on the left or add a comment to the Chemistry World blog