Carbon nanotubes are extremely effective as a means to detect potentially dangerous gases that may be present in the air. The previous methods used to make these carbon nanotube sensors have typically involved hazardous materials, though, and none of them could really be scaled up to a production level.
Researchers from MIT have now solved these problems, designing a simple and cheap way to fabricate these sensors. The answer? Simply writing with a ‘lead’ made of compressed carbon nanotubes.
The newly designed lead can be used in any regular mechanical pencil. By writing with it, you inscribe sensors on any paper surface.
This new sensor can detect extremely small quantities of ammonia gas, a major industrial hazard, in the air.
According to the lead researcher, Timothy Swager, the John D. MacArthur Professor of Chemistry, the sensors are easily adaptable, potentially being used to detect nearly any kind of gas.
“The beauty of this is we can start doing all sorts of chemically specific functionalized materials,” Swager says. “We think we can make sensors for almost anything that’s volatile.”
One significant advantage of this new fabrication process is how inexpensive it is. It’s considerably cheaper than other methods. The extreme stability of the “lead” is the other primary advantage. “You can’t imagine a more stable formulation. The molecules are immobilized,” says Swager.
The new research is published in the journal Angewandte Chemie.
Source: Massachusetts Institute of Technology
Image Credits: Jan Schnorr; Courtesy of Mark Hersam, Northwestern University