Optimised and percolated nanocomposite of polyaniline/tungstic anhydride modified electrode implemented in Vanadium redox flow battery

Abstract

In order to make vanadium redox flow batteries (VRFB) economically viable on a large scale, it is crucial to create graphite-based electrode nanomaterials with an excellent performance. In this research work, we synthesized the various percentage nanocomposites of polyaniline (PANI)/nano-tungsten oxide (NTO) by in situ chemical oxidative polymerization method. The impact of crystal phases, elements present in nanocomposites, thermal stability, surface analysis, and morphological factors were studied. We investigated electrochemical behavior such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and Tafel studies for PANI and NTO and prepared nanocomposites (NPATO) with different proportions sprayed over graphite felt (GF). Characterization analysis was used to examine the impact of various NTO loading concentrations on the PANI, and an ideal best percolated sample NPATO20/GF (3 mg cm−2) was inserted as a positive electrode in the cell stack to examine the charge–discharge cycles. At 60 mA cm−2 current density, their coulombic (η C), voltaic (η V), and energy (η E) efficiencies are outstanding. The concentration of 3 mg cm−2 nanoparticles on GF provided sufficient availability of active sites for electrochemical reactions, resulting in an increased electrochemical reaction. It has been proven that this work creates an affordable and efficient method for the forthcoming VRFBs.