New pocket-sized sensor can detect a silent threat in the air

 SO2 is a toxic air pollutant commonly released from vehicles and industrial emissions, and even minute exposure can cause serious health issues and long-term lung damage.  It is hard to detect before it has an adverse effect on health. Monitoring SO2 levels in real-time is crucial for public safety and environmental protection, yet existing technologies are often expensive, energy-intensive, or unable to detect the gas at trace levels.

To overcome this, scientists from Centre for Nano and Soft Matter Sciences (CeNS), Bengaluru, an autonomous institute of Department of Science and Technology (DST), fabricated a sensor by combining two metal oxides -- nickel oxide (NiO) and neodymium nickelate (NdNiO3), through a simple synthesis process. While NiO acts as the receptor for the gas, NdNiO3 serves as the transducer that efficiently transmits the signal, enabling detection at concentrations as low as 320 ppb, far surpassing the sensitivity of many commercial sensors.

To demonstrate the capabilities of this material, the team led by Dr. S. Angappane developed a portable prototype that incorporates the sensor for real-time SO2 monitoring.