QCM-Based HCl Gas Sensors Using Spin-Coated Aminated Polystyrene Colloids

Area of Science:

• Materials Science
• Chemical Sensing
• Environmental Monitoring

Background:

• Hydrogen chloride (HCl) gas poses significant health risks, necessitating effective detection methods in occupational settings.
• Existing polymer-based HCl gas sensors often lack cost-effectiveness and reusability.
• Development of novel, simple, and reusable sensing platforms is crucial for reliable HCl gas detection.

Purpose of the Study:

• To fabricate and characterize reusable HCl gas-sensing platforms using aminated polystyrene (a-PS) colloids.
• To evaluate the sensitivity, reusability, and selectivity of the developed a-PS colloidal sensors.
• To explore the potential of a-PS colloids as HCl sorbents in gas filters.

Main Methods:

• Fabrication of aminated polystyrene (a-PS) colloidal sensors.
• Utilizing quartz crystal microbalance (QCM) for sensing measurements.
• Assessing sensor performance through adsorption and selectivity tests.

Main Results:

• The a-PS(1.0) colloidal sensor with high amination degree showed the highest binding capacity (102 μg/mg).
• Achieved a sensitivity of 3.88 Hz/ppm and a limit of detection (LOD) of 5.002 ppm for HCl gas.
• Demonstrated higher sensitivity to HCl compared to formaldehyde (HCHO) and hydrogen fluoride (HF) due to selective binding affinity.

Conclusions:

• Aminated polystyrene (a-PS) colloids provide a highly sensitive and reproducible platform for HCl gas sensing.
• These a-PS colloidal sensors are reusable and cost-effective, suitable for workplace safety.
• a-PS colloids can also function as effective HCl sorbents in gas column filters.