High performance sulfonic acid doped polyaniline–polystyrene blend ammonia gas sensors

In this work, we present a method of preparation and sensing measurement of four camphorsulfonic acid (CSA) doped polyaniline–polystyrene blends (PANI–PS), where PANI is obtained by dispersion polymerization and blending is conducted by casting method. The effect of CSA concentrations on morphological, optical, thermal and electrical properties has been thoroughly analysed. Interestingly, the morphological analysis (SEM) exhibits different sizes of nanoparticle structures, whereas the FTIR spectra show chemical interaction between the two polymers. DSC data clearly reflects that the blend films carry combined physical properties of both the polymer components. The electrical properties are studied by in-plane I–V characteristics and four probe conductivity measurements. Finally, the blends with high conductivity seem to have good sensitivity and reversibility when used as NH3 sensors.