As can be imagined, finding a leak deep within the piping of someplace like a water treatment plant can be an arduous process. Thanks to ongoing research at the University of Washington, however, it could be about to get much easier. Scientists there have created electrically-conductive paper that senses water.
Led by Prof. Anthony Dichiara, a team of students produced the material using traditional paper-making techniques, but they mixed highly-conductive carbon nanotubes in with the usual wood fibers. At the time, their intention was simply to make paper that could conduct electricity, and they successfully did so.
When that paper was accidentally exposed to drops of water, however, its fibrous cells swelled up to three times their normal size. This displaced the nanotubes, disrupting the electrical current travelling through the paper. As a result, an LED light that was receiving power via the paper went out.
When the paper dried out afterwards, though, its conductive network reformed, allowing it to function normally once again.
Now, the team is envisioning electrically-wired sheets of the paper being wrapped around pipes in industrial settings. If any water were to leak out and dampen the paper in a particular location, an alarm would be triggered and a technician at a central control station would be notified.
Additionally, because the paper reacts to water specifically and not just any liquid, it could also be used to detect trace amounts of unwanted water in fuels.
A paper on the research was recently published in the Journal of Materials Chemistry A.
Source: University of Washington