Polypyrrole-coated electrospun polystyrene films as humidity sensors

Area of Science:

• Materials Science
• Chemical Engineering
• Sensor Technology

Background:

• Development of advanced materials for environmental monitoring is crucial.
• Resistive humidity sensors require materials with tunable properties.
• Polystyrene/polypyrrole composites offer potential for sensor applications.

Purpose of the Study:

• To prepare flexible polystyrene/polypyrrole (PS/PPy) mats.
• To evaluate their performance as resistive humidity sensors.
• To characterize the structural and sensing properties of the composite mats.

Main Methods:

• Electrospinning of polystyrene (PS) fibers.
• In situ chemical polymerization of pyrrole to form polypyrrole (PPy) on PS fibers.
• Characterization using FTIR, SEM, contact angle, and EIS.
• Testing sensor response, response/recovery times, and stability.

Main Results:

• Homogeneously distributed PS fibers with an average diameter of (1.04 ± 0.12) μm were obtained.
• Successful incorporation of PPy chains onto PS fibers confirmed by spectroscopy and microscopy.
• The PS/PPy mats showed a sensor response of 128.6% with fast response (54.9 ± 3.5 s) and recovery (76.8 ± 11.1 s) times.
• Stable sensor performance observed over several days under varying humidity conditions.

Conclusions:

• Flexible PS/PPy mats are successfully prepared using electrospinning and in situ polymerization.
• These composite mats demonstrate excellent performance as resistive humidity sensors, comparable to existing technologies.
• The materials show promise for practical applications in humidity sensing.