Porous flexible polyaniline/polyvinylidene fluoride composite film for trace-level NH3 detection at room temperature

Abstract Flexible, highly sensitive, selective, and room temperature ammonia (NH3) sensor based on porous polyaniline/polyvinylidene fluoride (PANI/PVDF) composite film was developed by an in-situ chemical oxidative polymerization process. The obtained flexible PANI/PVDF film showed a three-dimensional and hierarchical porous structure, which greatly enhanced the sensing performance of the PANI film sensor. It exhibited an excellent selectivity to NH3 at 25℃ with 110% response towards 5 ppm. Furthermore, the PANI/PVDF film sensor can detect 1 ppm NH3 (Response = 27%) along with excellent stability and response reproducibility. To 0.2 ppm NH3, the PANI/PVDF showed 6.5% response at 25℃. Furthermore, it also showed a good linearity relationship between the response and the concentration of NH3. Additionally, the PANI/PVDF film exhibited excellent bending stability, showing very little response value fluctuation at different bending angles. This work shows that the proposed PANI/PVDF film is promising for detecting trace-level NH3 at room temperature, and can be applied in real-time environmental monitoring.