Scientists build smartphone sensors that can detect NO2 air pollution
A team of researchers from RMIT University’s Center for Advanced Electronics and Sensors have come up with a breakthrough method that equips smartphones with special sensors to detect the amount of nitrogen oxide present in the air. It means that we might soon have accurate environmental data right at our disposal.
According to the World Health Organization (WHO), toxic air pollution is the cause of more than 7 million premature deaths every year. The gas accelerates the risk of respiratory diseases in children and senior citizens. The researchers have built sensors that are small and sensitive in nature, and can easily detect the amount of NO2 floating around us.
The biggest complexity of air pollution is that it is invisible, and we can’t feel the presence of harmful gases present. Placing NO2 detecting sensors in our smartphones could be a major step forward. In addition, scientists at the University of California, San Diego are also working towards developing their own portable sensors to detect NO2 in the air. The developments are being termed as the most affordable methods to quantify the presence of NO2 in the atmosphere to date.
Here’s how it works: The sensors detect the gas by absorbing nitrogen dioxide gas molecules onto flecks of the tin disulphide. The tin disulphide is a pigment that is yellowish-brown in color, and is generally used as paint for gilding, RMIT University said in a statement. For creating the sensors, researchers turned this material into flecks that are only as thick as a few atoms. The surface area of the flecks is good enough to absorb NO2 molecules in a highly selective manner for giving out an accurate reading.
Professor Kourosh Kalantar-Zadeh, who headed up the project, said that we could prevent ourselves from the harmful effect of nitrogen dioxide by having access to personal, sensitive, and reliable monitoring systems. “The revolutionary method we’ve developed is a great start to creating a handheld, low-cost and personalized NO2 sensor that can even be incorporated into smartphones,” Kalantar-Zadeh said. “Not only would it improve the quality of millions of people’s lives, but it would also help avoid illness caused by nitrogen dioxide poisoning and potentially even death.”
Kalantar-Zadeh developed the method with the help of fellow researchers and co-workers from the Chinese Academy of Sciences. The idea behind the development of this method was to give access of air pollution data to the public so that it can be used for prevention, the university said. The main reason behind the presence of NO2 in urban areas is thanks to the emission of smog from coal-burning plants and diesel engines, which Volkswagen recently got into a heap of trouble for disguising in its TDI lineup around the world.
The researchers are hopeful that an app to support the method will be developed soon. “A lack of public access to effective monitoring tools is a major roadblock to mitigating the harmful effects of this gas, but current sensing systems are either very expensive or have serious difficulty distinguishing it from other gases,” Kalantar-Zadeh said. “The method we have developed is not only more cost-effective, but it also works better than the sensors currently used to detect this dangerous gas.”
Source: Extreme Tech