Innovative Sensor Tech Targets Indoor Air Pollution
Indoor air pollution is an often overlooked threat to human health, stemming from everyday items like cleaning products, candles, and makeup. These common household items emit formaldehyde, a colorless and odorless chemical linked to various health risks. A team at Carnegie Mellon University (CMU) is addressing this issue with groundbreaking technology designed to enhance indoor air quality monitoring.
Albert Presto, the director of the Center for Atmospheric Particle Studies at CMU, emphasizes the importance of awareness about indoor pollutants to mitigate potential health hazards. The researchers have developed a low-cost solution that extends the lifespan of air quality sensors, enabling them to detect harmful formaldehyde levels more effectively.
The core of this innovation lies in the use of MXene, a class of compounds known for their energy storage and gas sensing capabilities. However, MXenes are prone to oxidation, especially when exposed to air or humidity, limiting their effectiveness as long-term air quality monitors.
Led by Reeja Jayan, a professor of mechanical engineering at CMU, the research team tackled this challenge by applying a unique polymer coating to the MXene sensors. This coating dramatically extends the sensor's half-life by over 200%, enabling it to regenerate its performance over time. The technique involves vaporizing materials to form a nano-coating on the sensor, akin to how condensation forms on a cold glass.
Initially, the MXene sensors had a lifespan of just over two months. With the polymer coating, they now last more than five months. Shwetha Sunil Kumar, a Ph.D. candidate in mechanical engineering, highlighted that the coating also enhances the sensor's ability to detect lower levels of formaldehyde.
Additionally, the team discovered that introducing humidity to the sensor at the end of its life allows it to recover approximately 90% of its sensing ability. Jayan is optimistic about the potential for this technology to be applied to other devices, such as batteries, to improve their longevity and safety.