Pioneering Sensing Solutions for In-Situ Monitoring of Volatile Organic Compounds in Soil and Groundwater Using Chemiresistor Sensor Technology

Abstract

The monitoring and classification of volatile organic compounds (VOCs) in soil and groundwater is a critical task in guaranteeing environmental protection and remediation of contaminated sites. Traditional methods of sample collection and off-site analysis could be expensive, laborious, and may not accurately represent in-situ conditions. To address these encounters, state-of-the-art sensing solutions using chemiresistor sensor technology have been developed for instantaneous, uninterrupted, and long-term monitoring of VOCs in the subsurface. The chemiresistor comprises of a chemically-sensitive polymer dissolved in a solvent and mixed with conductive carbon particles. The resultant ink is deposited onto thin-film platinum traces on a solid substrate. When VOCs come into interaction with the polymers, they are absorbed, initiating the polymers to swell and change the resistance of the electrode. This variation in resistance can be measured and recorded, providing information about the concentration of the VOCs.