Ultrahigh sensitive and selective room temperature operable poisonous carbon monoxide gas sensor based on polyaniline ternary composite

Abstract

In this research paper, the influence of vanadium pentoxide (V2O5) and lead tetroxide (Pb3O4) on poisonous carbon monoxide (CO) gas sensing performance of polyaniline (PANI) at ambient temperature was deliberately discussed. Through in-situ polymerization method, the PANI/ V2O5 + Pb3O4 (PVL) ternary composites was prepared by taking vanadium pentoxide and lead tetroxide in proportionate order of 10, 20, 30, 40 and 50 wt% with polyaniline. The synthesized composites were characterized and confirmed by using XRD, FTIR, SEM, HRTEM and TGA studies. To support the CO sensing, the DC conductive studies are carried out at the temperature range 20 to 200 0C. The PVL-3 (PANI/ V2O5 + Pb3O4 − 30 %) ternary composite has shown an increased conductivity compare to pristine PANI and other ternary composites. Using, DC conductivity graphs the activation energy was determined. For the CO gas sensing studies, the film of all the composites was prepared using spin coating unit. Among PANI and all the ternary composites, PVL-3 ternary composite has shown a good variation in resistance. This composite has shown a better sensitivity of 82 % at 25,000 PPMv level. Along with this the ternary composite has depicted an appreciable response time of 34 s a recovery time of 37 s. The sensing stability of the composite also tested for 60 days. The detailed CO sensing mechanism was discussed thoroughly.