New graphene nano-ribbons lend sensors unprecedented sensitivity

The team developed a new form of nano-ribbon made

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from graphene, a 2-D honeycomb of carbon atoms. When the researchers integrated a film of the nano-ribbons into the circuitry of a gas sensor, it responded about 100 times more sensitively to molecules than did sensors featuring even the best-performing carbon-based materials.

"We previously studied sensors based on other carbon-based materials such as graphene and graphene oxide," said Alexander Sinitskii, associate professor of chemistry at Nebraska. "In the case of graphene nano-ribbons, we were certain that we would see some sensor response, but we did not expect that it would be that much higher than anything we have seen in the past."

Reporting their findings in the journal Nature Communications, the researchers showed that gas molecules can dramatically alter the electrical resistance of nano-ribbon films. Different gases produced varying resistance signatures, allowing the sensor to distinguish among them.

"With multiple sensors on a chip, we were able to demonstrate that we can differentiate between molecules that have nearly the same chemical nature," said Sinitskii, a member of the Nebraska Center for Materials and Nanoscience. "For example, we can tell methanol and ethanol apart. So these sensors based on graphene nano-ribbons can be not only sensitive but also selective."

Read more at: https://phys.org/news/2017-10-graphene-nano-ribbons-sensors-unprecedented-sensitivity.html#jCp