High performance tube sensor based on PANI/Eu³⁺ nanofiber for low-volume NH₃ detection

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Polyaniline (PANI) is a conductive polymer with potential in gas sensing.
• Europium (Eu³⁺) ions can influence material morphology and properties.
• Developing sensitive and selective gas sensors for low-volume detection is crucial.

Purpose of the Study:

• To synthesize and characterize a novel polyaniline/Eu³⁺ nanofiber material.
• To fabricate a tube sensor using this material for ammonia (NH₃) gas detection.
• To evaluate the sensing performance, including response, recovery, reproducibility, and selectivity.

Main Methods:

• Preparation of polyaniline (PANI)/Eu³⁺ nanofiber sensing film using Eu(NO₃)₃ as a structure-directing agent.
• Characterization of material properties using Scanning Electron Microscope (SEM), Energy-Dispersive X-ray (EDX), Fourier Transform Infrared spectroscopy (FT-IR), X-Ray Diffraction (XRD), and Brunauer-Emmett-Teller (BET) techniques.
• Fabrication of a tube sensor by growing PANI/Eu³⁺ nanofibers onto the inner wall of capillary glass.

Main Results:

• A nanofiber-like network with a porous structure and large specific surface area was formed in PANI embedded with Eu³⁺ ions.
• The PANI/Eu³⁺ tube sensor demonstrated a high response (435%) to 0.25 ppm NH₃ gas at low volumes (0.3 mL).
• The sensor exhibited a short response time (5 s), recovery time (5 s), and excellent reproducibility and selectivity.

Conclusions:

• The PANI/Eu³⁺ nanofiber material possesses favorable characteristics for gas sensing applications.
• The developed tube sensor shows significant potential for the detection of low-volume ammonia gas.
• The integration of Eu³⁺ ions enhances the sensing performance of polyaniline-based materials.