Canadian researchers have built a tiny, working propeller out of gold and nickel nano-rods. It is not the first time a nanoscale rotor has been made, but previous efforts have involved a biological process, which this one does not.
The device is kept in solution, anchored to a silicon wafer. It spins when hydrogen peroxide is added to the solution. The H2O2 reacts with the nickel tips of the propeller. This causes bubbles to form, spinning the tiny blades at an almost constant speed.
Professor Geoffrey Ozin and colleagues at the University of Toronto discovered the behaviour by accident, according to the BBC. "Rotational motion is at the heart of many conventional machines, such as rotary engines, screws and clocks," Professor Ozin says. "However, these machines clearly need more than just a rotor."
The researchers don't quite have the tiny propeller under control yet: it can spin in either direction, and the researchers have spotted a variety of different kinds of motion. Critics argue that this means that it can't be considered a true nano-machine. ®