Dielectric and Humidity Sensing Properties in Iron Nanoparticle Substituted Polyaniline Composite

Abstract

The existence of graphene-based Polyaniline nanocomposite has been demonstrated to be exceptional host matrices for entrapping nano-sized particles, and its composites are widely used in a variety of applications such as transducers, sensors, electrodes, microwave absorption, and thermoelectric applications. The purpose of this study is to investigate the dielectric properties and humidity sensing response of a Fe doped PANI/Graphene (PAFG) composite synthesized in-situ polymerization using adhathoda vasica plant extract. The FT-IR, XRD, and SEM-EDX techniques were used to characterize the sample. The dielectric measurements were performed at 298K over a wide frequency range 5x101 to 5x106 Hz. Humidity response studies were performed at room temperature. Iron nanoparticles distributed homogeneously in the PANI matrix were ascertained from IR spectral data. At room temperature, the dielectric properties of the synthesized DS-4 powder outperform those of the synthesized pristine PANI and Fe nanoparticles, with superior dielectric constant and high dielectric loss. When the synthesized iron decorated composite was exposed between 10% and 97% RH, the electrical resistance decreased, which is attributed to the polarization process affecting electrical conductivity within these materials. The PAFG-40% composite exhibited high sensitivity at low humidity levels ranging from 30% to 70% RH.