Vanadium Oxide-Poly(3,4-ethylenedioxythiophene) Nanocomposite as High-Performance Cathode for Aqueous Zn-Ion Batteries: The Structural and Electrochemical Characterization

Abstract

In this work the nanocomposite of vanadium oxide with conducting polymer poly(3,4-ethylenedioxythiophene) (VO@PEDOT) was obtained by microwave-assisted hydrothermal synthesis. The detailed study of its structural and electrochemical properties as cathode of aqueous zinc-ion battery was performed by scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction analysis, X-ray photoelectron spectroscopy, thermogravimetric analysis, cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The initial VO@PEDOT composite has layered nanosheets structure with thickness of about 30–80 nm, which are assembled into wavy agglomerated thicker layers of up to 0.3–0.6 μm. The phase composition of the samples was determined by XRD analysis which confirmed lamellar structure of vanadium oxide V10O24∙12H2O with interlayer distance of about 13.6 Å. The VO@PEDOT composite demonstrates excellent electrochemical performance, reaching specific capacities of up to 390 mA∙h∙g−1 at 0.3 A∙g−1. Moreover, the electrodes retain specific capacity of 100 mA∙h∙g−1 at a high current density of 20 A∙g−1. The phase transformations of VO@PEDOT electrodes during the cycling were studied at different degrees of charge/discharge by using ex situ XRD measurements. The results of ex situ XRD allow us to conclude that the reversible zinc ion intercalation occurs in stable zinc pyrovanadate structures formed during discharge.

Power and Energy Optimization of Carbon Based Lithium-Ion Battery from Water Spinach (<i>Ipomoea Aquatica</i>)

“…Furthermore, X-Ray Diff raction Method (XRD) aims to characterize the crystallography of a sample through the peaks formed at an angle of 2θ diff ractogram (Volkov et al, 2022). In this study, the 2θ angle read in the formation of the peak ranged from 0° to 80° shown in Figure 2.…”

Vanadium oxide - poly(3,4-ethylenedioxythiophene) cathodes for zinc-ion batteries: effect of synthesis temperature

“…In this work, the structure, composition, and electrochemical performance of vanadium oxidebased composites with PEDOT obtained at two different temperatures of microwave-assisted synthesis have been studied for the first time. It was previously reported that such a modification method resulted in superior electrochemical performance [32,33]. The effect of the temperature of hydrothermal synthesis on the functional properties of the cathodes for aqueous zinc-ion battery was evaluated by different electrochemical techniques.…”