PANI@Ag nanocomposites gas sensors for rapid detection of ammonia

Schematic diagram of PANI@Ag nanocomposite films for gas sensor using spin coating. Preparation of Polyaniline and Ag@PANI nanocomposite with various concentrations of silver. XRD analysis to determine structural properties such as lattice parameters, strain, grain size, phase composition, and preferred orientation. FT-IR analysis to identification of functional groups within molecules where such groups vibrate (either through stretching or bending in various ways) when irradiated with specific wavelengths of light. Uv–visible spectroscopy analysis to obtain the absorbance spectra of a compound in the solution. FE-SEM analysis to observe structures of prepare samples. EDX analysis to determine the elemental composition of the sample. TGA analysis for knowing the stability temperature of compounds. At room temperature, samples were subjected to different concentrations of NH3 to study their gas-sensing capabilities. A thorough examination of the mechanisms involved and the impact of Ag on sensor ammonia sensing behaviours was carried out. [Display omitted] In this study, the selective ammonia gas sensing is achieved using nanocomposite films of polyaniline (PANI) along with different concentrations of silver. In order to study the gas-sensing capabilities of the samples, they were exposed to different concentrations of NH3 at room temperature after being immersed in the PANI matrix using the in-situ oxidative polymerization process. For PANI loaded with 0.2 g of Ag, a gas sensing response of 60 % was attained for 100 ppm of NH3 gas. Resistance, which was already strong before NH3 deprotonation, is amplified by combining PANI@Ag with nanocomposite porosity augmentation. Among the numerous compositions investigated thin films with a 0.5 g loading of Ag embedded in PANI matrix showed an exceptionally high level of selectivity towards NH3 gas at ambient temperature. The result sensor response was 77 % at 100 ppm, and their recovery time was shorter than 17 s. The designed sensor is more selective to NH3 gas compared to ethanol, CO, CO2, or H2S.