Conductive Polyaniline-Based Microwire Arrays for SO₂ Gas Detection

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Polyaniline-based conductive polymers offer excellent properties for electrochemical sensors.
• Sensor performance relies heavily on the precise structure and dimensions of these polymers.
• Uniformly arranged microwire arrays are challenging to fabricate using current methods.

Purpose of the Study:

• To develop a novel method for preparing uniformly arranged polyaniline microwire arrays.
• To investigate factors influencing microwire array formation.
• To demonstrate the gas sensing capabilities of the prepared polyaniline microwire arrays.

Main Methods:

• Utilized a combination of wettability interface dewetting and a liquid-film-induced capillary bridges method.
• Investigated the effects of solution concentration, template width, evaporation temperature, and time.
• Analyzed microwire formation rates using Scanning Electron Microscopy (SEM).

Main Results:

• Achieved a 100% microwire formation rate under optimized conditions (1.0 mg mL⁻¹ polyaniline, 10 μm silicon template, 80 °C, 18 h).
• Demonstrated room-temperature sulfur dioxide (SO₂) sensing with the prepared microwire arrays.
• Attained a fast response speed of approximately 20 seconds and a detection limit as low as 1 ppm for SO₂.

Conclusions:

• The liquid-film-induced capillary bridge method provides a new pathway for fabricating gas sensor devices from insoluble polymers.
• Uniformly arranged polyaniline microwire arrays are effective for sensitive and rapid SO₂ detection.
• This technique holds promise for developing advanced gas sensor applications.