MIT engineers have discovered a new way to generate electricity using tiny carbon particles that can create a current by interacting with a surrounding liquid. That liquid, an organic solvent, draws electrons away from the particles, thus generating a current that can be used to drive chemical reactions or to power micro or nano robots, say the researchers.
“This mechanism is new and this new way of generating power is completely new,” says Michael Strano , Professor of Chemical Engineering at MIT. “This technology is intriguing because all you have to do is create a solvent fluid on the basis of those particles. That allows you to do electrochemistry, but without cables.”
In a new study describing that phenomenon, researchers have shown that you can use that electrical current to cause a reaction known as alcohol oxidation — an organic chemical reaction that’s important to the chemical industry.
Strano is the senior author of the research, published June 7, 2021, in Nature . Communications . The lead authors of the study are MIT graduate Albert Tianxiang Liu and former MIT researcher Yuichiro Kunai . They also sign as authors Anton Cottrill (former graduate student), Amir Kaplan and Hyunah Kim (post doctoral students), Ge Zhang ( graduate student ), and Rafid Mollah and Yannick Eatmon (recent graduates).
A new technology
The new discovery stemmed from Strano ‘s research on carbon nanotubes – hollow tubes made up of a network of atoms that possess a unique electrical property. In 2010, Strano demonstrated for the first time that carbon nanotubes can generate “thermopower waves.”
Strano ‘s work led his students to discover a related feature of carbon nanotubes. They found that when a part of the nanotube is coated with a Teflon-like polymer, it creates an asymmetry that makes it possible for the electrodes to flow from the coated to the uncoated part of the tube, generating an electrical current. Those electrodes can be attracted by immersing the particles in a solvent that is hungry for electrons.
To harness that special ability, the researchers created electricity-generating particles by placing carbon nanotubes on a sheet of paper-like material. One side of that sheet is coated with the Teflon-like polymer, and the researchers then cut out tiny particles, which can vary in size and shape. For this study, they made particles whose dimensions were 250 microns by 250 microns.
