Handheld Device for Selective Benzene Sensing over Toluene and Xylene

Area of Science:

• Environmental Science
• Analytical Chemistry
• Materials Science

Background:

• Benzene is a carcinogen found in consumer products and from organic combustion.
• Current benzene monitoring faces challenges due to the inaccuracy of low-cost sensors.
• Strict regulatory limits for benzene exist, necessitating reliable detection methods.

Purpose of the Study:

• To develop a compact, battery-driven device for selective benzene detection.
• To overcome the limitations of existing sensors in accuracy and selectivity.
• To enable accurate benzene monitoring for personal exposure assessment and environmental regulation.

Main Methods:

• Utilized a chemoresistive Pd/SnO2 sensor.
• Incorporated a packed bed of catalytic WO3 nanoparticles as a prescreening layer.
• Tested the device's selectivity against various interfering gases and robustness to relative humidity.

Main Results:

• Achieved unprecedented selectivity (>200) for benzene over common interferents.
• Detected benzene down to 13 ppb with high accuracy.
• Demonstrated superior robustness to relative humidity (10-80%).
• Quantified indoor benzene levels, correlating well with mass spectrometry (R² ≥ 0.94).

Conclusions:

• The developed device offers a reliable and accurate method for benzene detection.
• Its compact and robust design is suitable for personal exposure monitoring.
• This technology can aid in implementing low-emission zones and ensuring environmental sustainability.