Fussy nanofibrous network of polyaniline (PANi) for NH_3 detection

摘要

Fuzzy nanofibrous network of polyaniline thin film is successfully synthesized for ammonia gas detec tion application. The nanofiber network of polyaniline thin film is characterized using Fourier transform infrared (FT-IR) spectroscopy, field emission scanning electron microscope (FESEM), transmission electron microscope and optical absorption studies. Network of polyaniline is highly porous with inter connected fuzzy nanofibers having diameter typically between 70 and 75 nm. The gas sensing properties of polyaniline film are tested at room temperature (300 K). The PANi sensor showed selectivity for NH3 over H_2S compared to NO_2 (S_(NH_3) /S(H_2S = 48 and S_(Nh_3 /S_(NO_2 = 24). The maximum gas response of 96% was achieved with 96.88% stability for PANi films upon exposure of l00 ppm NH_3 at room temperature. The response and recovery times changed significantly with the NH3 concentration. The increased NH_3 con centration affected the response and recovery times; the response time decreases from 427 to 122 s with an increase in recovery time from 180 to 1245 s.