A polypyrrole-based ammonia-detection gas sensor was studied in this work. Under a 1.6 V electrodeposition potential, polypyrrole (PPy) was electrochemically synthesized from an aqueous solution of 0.1 M pyrrole and 0.1 M oxalic acid. An extension to the polypyrrole films was applied through electrochemical deposition on indium tin oxide (ITO), using the metal oxide nanoparticles of MgO and WO3. These films were investigated for their sensing behavior towards NH3 at different working temperatures and different weight percentages of nanoparticles .The measurements of A.C conductivity were conducted over a frequency range of 101-105 Hz and temperature range of 298-423 K . The highest electrical conductivity was equal to 3.67x10-1 Ω.cm-1 at a temperature of 323 K and frequency of 105H z. The experimental results showed that the sensitivity of the undoped and doped PPy with nanoparticle films to ammonia gas changes with the change in temperature and weight percentage.

The study involves the synthesis of PPy and PPy loaded with various metal oxides TiO2, WO3, Fe2O3, and SnO2 with different ratios by polymerization procedure. The UV-Visible analysis was carried in the wavelength range (300-1100nm) to determine the optical parameters like optical energy gap and optical constants. From the analysis of absorption spectra, the band gaps of polypyrrole undoped are 1.85eV While the samples of PPy/SnO2 composite gained the highest values 2.2eV at weight Percentage (5%) but with PPy/Fe2O3 gained lowest values 1.5eV at weight Percentage (1%).