Sensing Characteristics of Nanostructured PANI/Ag Thin Films as H2S Gas Sensor

Abstract

Abstract Nanocomposites of polyaniline (PANI) and Silver (Ag) nanoparticles (NPs) have been successfully synthesis using hydrothermal and chemical method respectively. The nanocomposite films were deposited by spin coating technique on Si substrates and examined using XRD, FE-SEM, EDX, FT-IR techniques as well as their sensing properties were studied towards H2S gas. The XRD pattern showed a presence of crystalline nature of PANI NFs film and cubic structure of PANI/Ag films. FE-SEM images revealed that PANI film has nanofibers structure, whereas the PANI/Ag films composite revealed that Ag NPs caped with PANI nanofiber. The sensing analysis indicated that on exposure to H2S gas at low concentration 25 ppm, it was observed that the PANI/Ag films sensor composite showed high sensitivity compared with pure PANI NFs, and the maximum sensitivity (73.35%) was obtained at 200 °C with faster response/recovery times < 1 sec.