Preparation, characterization and CO2 gas sensitivity of Polyaniline doped with Sodium Superoxide (NaO2)

The sodium superoxide was prepared in single step method by heating sodium nitrate (NaNO3) in oxygen rich environment. The PANi/NaO2 composites were prepared using Ex-situ technique range from 5-20 wt.%. The crystallinity and structure morphology of the PANi/ NaO2 composite films were characterized by X-ray diffraction, Scanning electron microscopy and Fourier transform infrared spectroscopy respectively. The sensor response was estimated by the change in electrical resistance of sensor in presence of CO2 gas. The sensor response and selectivity for pure PANi and doped PANi/NaO2 sensors as a function of concentration of CO2 at room temperature has been systematically studied. The sensors show better performance towards the CO2. A significant sensitivity and fast response toward CO2 observed for the 20 wt.% PANi/NaO2 composite film. The sensing response curve assign to transition from n-type to p-type behavior of samples. (C) 2015 Published by Elsevier Ltd.