Electrochemical template-free synthesis of nanofibrous polyaniline modified electrode for ascorbic acid determination

Abstract

Electrochemical formation of polyaniline (PANI) modified electrode was performed galvanostatically from aqueous solution of 1.0 mol dm-3 HCl containing 0.2 mol dm-3 aniline at current densities ranging from 0.5-3.0 mA cm-2. The morphology of PANI electrode consisted of highly developed nanofibrous network with electrocatalytic features towards oxidation of ascorbic acid, reflected in increase of the peak current ~ 2.5 times and shift of the oxidation potential by 0.32 V to less positive values. Response of PANI modified electrode was obtained from anodic LSV curves. Current peak potentials decreased with increase of pH with slope of ~ 32 mV pH-1, indicating two electron charge transfer process with liberation of one proton characteristic of an electrochemical reaction followed by a chemical step. © 2015 The Authors.