A Study of Methylcellulose Based Polymer Electrolyte Impregnated with Potassium Ion Conducting Carrier: Impedance, EEC Modeling, FTIR, Dielectric, and Device Characteristics

Abstract

In this research, a biopolymer-based electrolyte system involving methylcellulose (MC) as a host polymeric material and potassium iodide (KI) salt as the ionic source was prepared by solution cast technique. The electrolyte with the highest conductivity was used for device application of electrochemical double-layer capacitor (EDLC) with high specific capacitance. The electrical, structural, and electrochemical characteristics of the electrolyte systems were investigated using various techniques. According to electrochemical impedance spectroscopy (EIS), the bulk resistance (Rb) decreased from 3.3 × 105 to 8 × 102 Ω with the increase of salt concentration from 10 wt % to 40 wt % and the ionic conductivity was found to be 1.93 ×10−5 S/cm. The dielectric analysis further verified the conductivity trends. Low-frequency regions showed high dielectric constant, ε′ and loss, ε″ values. The polymer-salt complexation between (MC) and (KI) was shown through a Fourier transformed infrared spectroscopy (FTIR) studies. The analysis of transference number measurement (TNM) supported ions were predominantly responsible for the transport process in the MC-KI electrolyte. The highest conducting sample was observed to be electrochemically constant as the potential was swept linearly up to 1.8 V using linear sweep voltammetry (LSV). The cyclic voltammetry (CV) profile reveals the absence of a redox peak, indicating the presence of a charge double-layer between the surface of activated carbon electrodes and electrolytes. The maximum specific capacitance, Cs value was obtained as 118.4 F/g at the sweep rate of 10 mV/s.

Studies of Circuit Design, Structural, Relaxation and Potential Stability of Polymer Blend Electrolyte Membranes Based on PVA:MC Impregnated with NH4I Salt

“…The fitting parameters for the EEC and DC conductivity values are listed in Table 1 and Table 2 , respectively. The R b is calculated by intercepting the real and spike axes [ 60 ]. Figure 2 shows polymer electrolyte structure and proposed ion conduction mechanism in the PVA:MC:NH 4 I electrolyte system.…”

Impedance and Dielectric Properties of PVC:NH4I Solid Polymer Electrolytes (SPEs): Steps toward the Fabrication of SPEs with High Resistivity

“…To examine dipole relaxation in polymeric materials, dielectric relaxation spectroscopy was accomplished over a large frequency range [ 29 ]. Using the following equations, the real and imaginary parts of ε * and M * may be calculated from the real ( Z ′) and imaginary ( Z ″) parts of Z * [ 9 , 30 , 31 ]: …”

“…It is worth mentioning that a low-density dielectric material configuration correlates to a low-density component [ 4 ]. Previous studies demonstrated that salt added into polymers such as chitosan, methylcellulose, dextran, polyethylene oxide, and polyvinyl alcohol are crucial to reducing the resistivity of polar polymers and increasing the DC conductivity owing to salt dissociation by the host polymer functional groups [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. Herein, the material of use is PVC host polymer that experiences several different behaviors, making it remarkably different from that previously reported for polymer electrolyte (PEs) materials.…”

An Investigation into the PVA:MC:NH4Cl-Based Proton-Conducting Polymer-Blend Electrolytes for Electrochemical Double Layer Capacitor (EDLC) Device Application: The FTIR, Circuit Design and Electrochemical Studies

“…To our knowledge, PEs appear as materials of interest that possess the required conductivity, as well as electrochemical stability [ 1 , 2 , 3 ]. For example, dimensional stability, durability, a relatively wide potential window (usually above 1.5 V), and its eco-friendly nature are all properties of these materials [ 4 ]. The characterizations of PEs are highly required because of its utilization in multidisciplinary fields, such as electrochemistry, polymer science, organic chemistry, and inorganic chemistry [ 5 ].…”