Tiny motors can tackle rising carbon dioxide levels

Nanoengineers, including one of Indian-origin, have designed tiny machines - smaller than the width of a human hair - that rapidly zoom around in water, remove carbon dioxide and convert it into a usable solid form.

"We are excited about the possibility of using these tiny enzyme-functionalised micromotors to combat ocean acidification and global warming," said study co-author Virendra V Singh, postdoctoral scientist from the University of California-San Diego.

The micromotors are essentially six-micrometer-long tubes that help rapidly convert carbon dioxide into calcium carbonate - a solid mineral found in egg shells, the shells of various marine organisms, calcium supplements and cement.

According to lead researcher and professor Joseph Wang, the proof of concept study represents a promising route to mitigate the buildup of carbon dioxide - a major greenhouse gas in the environment.

In their experiments, nanoengineers demonstrated that the micromotors rapidly decarbonated water solutions that were saturated with carbon dioxide.

Within five minutes, the micromotors removed 90 percent of the carbon dioxide from a solution of deionised water.

The micromotors were just as effective in a sea water solution and removed 88 percent of the carbon dioxide in the same time frame.

"In the future, we could potentially use these micromotors as part of a water treatment system, like a water decarbonation plant," noted Kevin Kaufmann, undergraduate researcher in Wang's lab.

"If the micromotors can use the environment as fuel, they will be more scalable, environmentally friendly and less expensive," Kaufmann suggested.

The work was published in the journal Angewandte Chemie.