Conductive, Acid-Doped Polyaniline Electrospun Nanofiber Gas Sensing Substrates Made Using a Facile Dissolution...

Area of Science:

• Polymer Science
• Materials Science
• Chemical Engineering

Background:

• High-performance polymers like polyaniline (PANi) are challenging to dissolve at high concentrations.
• Developing stable solutions is crucial for advanced applications such as sensing and nanofiber fabrication.
• Polyaniline doped with (+)-camphor-10-sulfonic acid (CSA) offers unique conductive properties.

Purpose of the Study:

• To report a novel dissolution method for high-concentration, high-molecular-weight polyaniline (PANi) doped with CSA.
• To enable the fabrication of PANi-CSA nanofibers for gas sensing applications.
• To evaluate the performance of PANi-CSA nanofiber membranes in colorimetric ammonia detection.

Main Methods:

• A simple one-pot method was developed to prepare 12-16 wt % solutions of 65,000 Da PANi-CSA in N,N-dimethylformamide.
• The resulting PANi-CSA solutions were processed into nanofibers using a single-nozzle electrospinning technique.
• The electrospun PANi-CSA nanofibrous membranes were utilized as substrates for colorimetric gas sensing.

Main Results:

• Achieved total solvation of high-concentration, high-molecular-weight PANi-CSA.
• Successfully fabricated PANi-CSA nanofibers and membranes via electrospinning.
• Demonstrated linear response of the PANi-CSA nanofiber sensors to ammonia concentrations ranging from 50 to 5500 ppm.
• Confirmed sensor linearity at both ambient (50% RH) and high (80% RH) humidity levels.

Conclusions:

• The novel dissolution method facilitates the processing of high-concentration PANi-CSA solutions.
• Electrospun PANi-CSA nanofibers provide a viable platform for sensitive and linear colorimetric ammonia sensing.
• The developed sensing membranes exhibit robust performance across a range of humidity conditions.