Abstract
In this study, plasticized films of polyvinyl alcohol (PVA): chitosan (CS) based electrolyte impregnated with ammonium thiocyanate (NH4SCN) were successfully prepared using a solution-casting technique. The structural features of the electrolyte films were investigated through the X-ray diffraction (XRD) pattern. The enrichment of the amorphous phase with increasing glycerol concentration was confirmed by observing broad humps. The electrical impedance spectroscopy (EIS) portrays the improvement of ionic conductivity from 10−5 S/cm to 10−3 S/cm upon the addition of plasticizer. The electrolytes incorporated with 28 wt.% and 42 wt.% of glycerol were observed to be mainly ionic conductor as the ionic transference number measurement (TNM) was found to be 0.97 and 0.989, respectively. The linear sweep voltammetry (LSV) investigation indicates that the maximum conducting sample is stable up to 2 V. An electrolyte with the highest conductivity was used to make an energy storage electrical double-layer capacitor (EDLC) device. The cyclic voltammetry (CV) plot depicts no distinguishable peaks in the polarization curve, which means no redox reaction has occurred at the electrode/electrolyte interface. The fabricated EDLC displays the initial specific capacitance, equivalent series resistance, energy density, and power density of 35.5 F/g, 65 Ω, 4.9 Wh/kg, and 399 W/kg, respectively.
Highlights
The development of electrochemical devices such as batteries, and electrical double-layer capacitors (EDLCs) has attracted the attention of many researchers, because of their wide applications in portable devices [1]
X-ray diffraction patterns were recorded for understanding the structural changes of polyvinyl alcohol (PVA): CS: NH4 SCN system upon the addition of glycerol plasticizer
The diffractogram of the un-plasticized film as depicted in Figure 1 displays a crystalline narrow peak that belongs to the NH4 SCN added salt at (2θ = 29.9◦ ) [34,35]
Summary
The development of electrochemical devices such as batteries, and electrical double-layer capacitors (EDLCs) has attracted the attention of many researchers, because of their wide applications in portable devices [1]. The most favorable electrochemical storage devices are EDLCs with higher energy properties [2]. EDLC is an energy storage device that supplies electricity via producing an electrical double layer consisting of an adsorbed layer of anions and cations at the electrolyte/the electrodes interfaces. The EDLC with relatively high conductive polymer as electrolytes and electrode separators, might be a potential substitute for other types of charge storage devices [4]. EDLC has attracted much attention because of its unique properties like durability, speedy charge-discharge rate, higher energy density, reversibility, and improvement in safety, which make it a good candidate for a wide range of applications [5]. Liquid electrolyte exhibits high ionic conductivity, there is a leakage problem and corrosion while gel and solid-state electrolytes overcome these drawbacks, and they are considerably preferred in EDLCs [9]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have