On the electrochemical synthesis and charge storage properties of WO3/polyaniline hybrid nanostructures

Abstract

The aim of this study is to tailor the electrochemical synthesis of hybrid materials consisting of nanoporous tungsten trioxide (WO3) and polyaniline (PANI) for application as supercapacitor electrodes. Nanoporous WO3, synthesized by the anodization of tungsten foils, acted as the active material framework for this assembly. With the variation of the anodization voltage, host materials with different morphological features were prepared. Subsequently, electrodeposition of PANI was carried out by potentiodynamic cycling in highly acidic media. Through alteration of the number of deposition cycles, the amount of deposited PANI was varied. This parameter had a decisive impact on the morphology of the resulting hybrids as confirmed by SEM images. Cyclic voltammetry and galvanostatic charge–discharge measurements were carried out to characterize the charge storage properties of the synthesized hybrids. By comparing electrochemical data with structural properties, structure–property relationships were established, and under optimal conditions, 350 F g−1 and 200 mF cm−2 were obtained.