Biphenyl-rGO composite room temperature gas sensor for enhanced amine sensing

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Amines, classified as volatile organic compounds (VOCs), are crucial in environmental monitoring, food safety, and healthcare.
• Current amine detection methods often rely on complex, expensive equipment.
• There is a need for portable, cost-effective, and sensitive amine detection technologies.

Purpose of the Study:

• To develop a cost-effective, room-temperature chemoresistive gas sensor for detecting specific amines.
• To utilize a biphenyl-reduced graphene oxide (B-rGO) composite to enhance sensor performance.
• To address limitations of low sensitivity, selectivity, and long-term instability in conventional amine sensors.

Main Methods:

• Fabrication of a chemoresistive B-rGO gas sensor using ultrasonic spray deposition.
• Optimization of sensor parameters, including flow rate and solvent evaporation.
• Testing sensor performance for ammonia, dimethylamine (DMA), trimethylamine (TMA), and total volatile basic nitrogen (TVB-N).

Main Results:

• The B-rGO sensor achieved a sensitivity of ~3500 and selectivity >30 for TVB-N.
• Highest sensitivity (~836) was observed for 100 ppm ammonia, with sensitivity order: ammonia > DMA > TMA.
• The B-rGO sensor exhibited significantly higher amine sensitivity (~7x) compared to rGO.
• The sensor demonstrated stability across temperature fluctuations (<50°C) and maintained performance for over 3 months.
• Sensor calibration curves showed an average R-squared value of 0.98.

Conclusions:

• The developed B-rGO chemoresistive sensor is a promising, cost-effective, and stable solution for amine detection at room temperature.
• The biphenyl modification significantly enhances the sensitivity and selectivity of reduced graphene oxide for amine sensing.
• This technology offers potential advancements in environmental monitoring, food safety, and diagnostic applications.