A new type of carbon nanotube could allow researchers to create handheld sensors that could sniff out bombs and drugs more quickly.
Carbon nanotubes are extremely strong and have high electrical conductivity, they are often used in sports products such as baseball bats and touchscreen computer displays, the University of Utah reported.
The researchers hope to build prototype handheld sensors and commercial scanners using these new nanotubes by the end of the year. The recent innovation could also lead to flexible solar panels that could be more easily stored or even "painted" onto surfaces.
The researchers discovered a way to break up bundles of carbon nanotubes using a polymer and deposit a microscopic amount of electrodes on a prototype handheld scanner that can detect toxic gases, drugs, or explosives. Once the sensor detects molecules from the target substance they alter the electric current through the nanotube material, signaling its presence.
"You can apply voltage between the electrodes and monitor the current through the nanotube," said co-founder Ling Zang, a professor of materials science and engineering and senior author of a study. "If you have explosives or toxic chemicals caught by the nanotube, you will see an increase or decrease in the current."
By modifying the surface of nanotubes with polymer the material can be programmed to detect a number of substances including those used in homemade bombs and about two dozen toxic gases.
"[The new device] could be used by the military, police, first responders and private industry focused on public safety," Zang said.
Most modern detectors analyze the spectra of ionized molecules of explosives or chemicals. This new technology is superior because it: it is more sensitive; it is more accurate; it has a faster response time; and it is cost effective because of its tiny size.
The findings were published Nov. 4 in the journal Advanced Materials.
