Sensor Breakthrough Could Enable Smartphones To Detect Air Pollution

Nitrogen dioxide is a component of inner-city smog caused by car exhausts and burning fossil fuels. Exposure for as little as 30 minutes can lead to airway inflammation, which is bad news for people with asthma and pretty much anyone who has a pair of lungs. As urban populations rise and we continue to burn vast amounts of fossil fuels, air pollution – which estimated to cause 3 million premature deaths a year – still remains a massive problem.

However, in a paper published this week in ACS Nano, scientists at the RMIT University in Australia and the Chinese Academy of Sciences have shown tin disulfide’s ability to detect nitrogen dioxide. A sensor, made with a thin film of tin disulfide just a few atoms thick, absorbs nitrogen dioxide gas molecules which can then be measured.

Other materials can attract nitrogen dioxide, however they find it hard to distinguish between other gases. Tin disulfide solely attracts particles of nitrogen dioxide which means it can provide more definite and accurate results.

"This was a magic material," Kourosh Kalantar-zadeh, a scientist on the project, told Mashable Australia. "The surface of this material has a nice energy that attracts nitrogen dioxide gas molecules selectively onto the surface."

Kalantar-zadeh went on to the say that he hopes this type of sensor could make its way into smartphones in the future, as it can be made small enough and only costs 1 Australian dollar (around 70 cents, or 50 pence) to manufacture. 

"This is why we put it in the public domain, to make sure people benefit right now, today," he said. "Anyone can go ahead and start making it."

The data from thousands of smartphone paired with geo-tracking data could enable governments and non-profit organizations to obtain and release real-time data on air quality in cities.

[H/T: Mashable Australia]

^{Main image credit: Lei Han/Flickr. (CC BY-NC-ND 2.0)}