On the Hydrogen Peroxide Sensing employing Fibres composed of Polyvinyl alcohol (PVA) and Polyaniline (PANI)

Abstract

The sensitivity of an electrocatalyst depends upon the kinetics of electrochemical reactions occurring at its surface. In this work, we prepared the polyvinyl alcohol (PVA) and polyaniline (PANI) nanofibres using a facile and cost-effective electrospinning method. We observed that the fibres composed of PANI and PVA exhibited efficient sensing of hydrogen peroxide (H2O2) as compared to the fibres prepared employing PVA alone. At low concentration of H2O2, a two-fold enhancement in the sensing activity is noticed in case of the fibre prepared using PVA-PANI (as compared to PVA fibres). On the other hand, at higher concentration, the sensitivity is around five times high. The enhancement in the sensing activity for PVA-PANI nanofibres is due to the increase in conductivity and electrochemical surface area upon addition of conducting PANI. The increased conductivity enhances the surface energy of the fibre and increased electrochemical surface area enhances the number of reactive sites, which results in enhanced sensing activity. The above analysis is further supported via the impedance analysis showing lower charge transfer resistance for PVA-PANI sample.