The miniaturization of electronic devices plays a fundamental role in the development of modern technologies and makes it possible to manufacture smaller and more powerful devices.
One of the main challenges in realizing the true potential of the functional nanomachine is to integrate and transmit motion with high precision.
Molecular gear systems make it possible to integrate multiple movements in a correlative way to transfer movements from one place to another and change their speed and direction.
However, there is currently no powerful method to apply the active driving of gear motions at the molecular scale.
Now, a team of researchers from the Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have successfully built the world’s smallest drive sprocket with its corresponding counterpart. According to the researchers, the nanogear is the first that can be actively controlled and piloted.
The molecular gear is only 1.6 nm, about 50,000th the thickness of a human hair, the smallest of its kind.
The research team managed to actively drive a molecular cogwheel and its counterpart, solving a fundamental problem in building nanoscale machines.
It consists of two closely related components composed of only 71 atoms. One of the components is a tryptic molecule which is similar in structure to a propeller or a bucket wheel. The second component is a flat fragment of a thioindigo molecule, similar to a small plaque. If the plate rotates 180º, the propeller only rotates 120º, resulting in a gear ratio of 2:3.
The nanoreductor is controlled by light, making it a molecular photogenerator. The tryptic plate and helix move in a locked and synchronized rotation as they are directly powered by light energy. Heat alone was not enough to spin the gear, as the FAU team discovered. When the researchers heated the solution around the gear in the dark, the propeller spun, but the plate didn’t: the gear “slipped.” The researchers thus concluded that the nanoreducer can be activated and controlled by a light source.
More information: www.nature.com