Portable Sensor to Detect Toxic SO₂ Gas

In July 2025, Researchers at the Centre for Nano and Soft Matter Sciences (CeNS), Bengaluru, created a low-cost, portable sensor capable of detecting sulfur dioxide (SO₂) at extremely low concentrations, paving the way for better air quality monitoring.

Key Points

Health Hazard: Sulfur dioxide, released from vehicles and industrial activity, causes respiratory issues and long-term lung damage even at low exposure levels.
Limitations of Existing Systems: Current SO₂ monitoring devices are often expensive, bulky, and lack sufficient sensitivity for early detection.
CeNS Innovation: The sensor combines nickel oxide (NiO) and neodymium nickelate (NdNiO₃)—with NiO detecting the gas and NdNiO₃ amplifying the signal.
High Sensitivity: The system detects SO₂ levels as low as 320 parts per billion (ppb), surpassing many commercial sensors.
Portable Prototype: A user-friendly device featuring real-time feedback and a color-coded alert system—green (safe), yellow (warning), red (danger).
Wide Application: Ideal for urban areas, industrial zones, and enclosed spaces, where constant air quality checks are crucial.
Public Health Boost: Offers an early warning solution to mitigate health risks, contributing to environmental safety and public awareness.