Synthesis and Characterization of Polyaniline Doped with HCl, H2SO4 and PVA as Secondary Dopant for Toxic Gas (Ammonia) Sensor

Abstract

In the present work, by simple chemical polymerization technique, H2SO4 (Sulphuric acid), HCl (Hydorochloric acid), poly (vinyl sulphonic acid) and PVA on PMMA substrate have been successfully synthesized PANI films for ammonia gas sensing. The polyaniline (PANI) thin films were synthesized by simple chemical polymerization technique, H2SO4 (Sulphuric acid), HCl (Hydorochloric acid), poly (vinyl sulphonic acid) and PVA on PMMA substrate as dopant. The ratio of monomer, dopant, and oxidant and reaction temperature has been optimized for better surface morphology of the synthesized PANI film. Scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis), and Fourier transforms infrared spectroscopy (FTIR) is used for characterization of synthesized thin films of PANI. Also the response of the films towards ammonia gas (in the range from 20 to 250 ppm) is carried out. It was observed that these process parameters i.e. ratio of monomer, oxidants, doping acids, and deposition time and reaction temperature has major effect on the surface morphology of PANI film. The synthesized thin film structures of polyaniline doped with HCl, H2SO4 and PVA on polymethylmethacrylate (PMMA) shows the response to ammonia gas sensing in the range 20ppm-250ppm and can be used for ammonia sensing application.