European researchers have developed what they say is the world’s smallest car, out of molecules.
The nano car, which at 4 nanometres long and 2 nanometres wide is about 500 million times smaller than a Volkswagen Golf, is propelled forwards by four electrically driven “wheels” on a copper surface.
The Dutch and Swiss researchers synthesised an organic molecule out of “motor proteins” kinesin and actin. The molecule is sublimated on to the copper and a Scanning Tunnel Microscope tip placed over it. Voltage is applied and electrons “tunnel” through the molecule, generating reversible structural changes in each of the four motor units. If all four wheels turn simultaneously, the car travels forward.
The researchers say this prototype symbolises lightweight construction at its most extreme.
Karl-Heinz Ernst, from the Swiss Federal Laboratories for Materials Science and Technology (EMPA) said that the synthesis of the molecule has brought Europe one step closer to the development of articificial nanoscale transport systems: “To do this, our car needs neither rails nor petrol; it runs on electricity.
“It must be the smallest electric car in the world — and it even comes with a four-wheel drive.”
The next challenge for the nano car is to improve its refuelling capacity. According to the researchers, the car needs to be “refilled” with power after every half revolution of the wheels. Its molecular design also limits the wheels’ turning ability; it can only turn in one direction. “In other words, there’s no reverse gear,” Professor Ernst explained.
The project involves researchers from the University of |Zurich in Switzerland as well as EMPA, and the University of Groningen and the University of Twente in the Netherlands and was part-funded through a European Research Council grant of €2.18 million for the development of Molecular Motors. The research was presented in the journal Nature this month.