Structural, Impedance, and EDLC Characteristics of Proton Conducting Chitosan-Based Polymer Blend Electrolytes with High Electrochemical Stability

Abstract

In this report, a facile solution casting technique was used to fabricate polymer blend electrolytes of chitosan (CS):poly (ethylene oxide) (PEO):NH4SCN with high electrochemical stability (2.43V). Fourier transform infrared (FTIR) spectroscopy was used to investigate the polymer electrolyte formation. For the electrochemical property analysis, cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical impedance spectroscopy (EIS) techniques were carried out. Referring to the FTIR spectra, a complex formation between the added salt and CS:PEO was deduced by considering the decreasing and shifting of FTIR bands intensity in terms of functional groups. The CS:PEO:NH4SCN electrolyte was found to be electrochemically stable as the applied voltage linearly swept up to 2.43V. The cyclic voltammogram has presented a wide potential window without showing any sign of redox peaks on the electrode surface. The proved mechanisms of charge storage in these fabricated systems were found to be double layer charging. The EIS analysis showed the existence of bulk resistance, wherein the semicircle diameter decreased with increasing salt concentration. The calculated maximum DC conductivity value was observed to be 2.11 × 10−4 S/cm for CS:PEO incorporated with 40 wt% of NH4SCN salt. The charged species in CS:PEO:NH4SCN electrolytes were considered to be predominantly ionic in nature. This was verified from transference number analysis (TNM), in which ion and electron transference numbers were found to be tion = 0.954 and tel = 0.045, respectively. The results obtained for both ion transference number and DC conductivity implied the possibility of fabricating electrolytes for electrochemical double layer capacitor (EDLC) device application. The specific capacitance of the fabricated EDLC was obtained from the area under the curve of the CV plot.

The Study of Plasticized Amorphous Biopolymer Blend Electrolytes Based on Polyvinyl Alcohol (PVA): Chitosan with High Ion Conductivity for Energy Storage Electrical Double-Layer Capacitors (EDLC) Device Application

“…Shukur et al [ 75 ] fabricated EDLC with activated carbon using CS: NH 4 Br: Glycerol, which obtained 7.5 F/g from CV analysis at scan rate of 10 mV/s. Also, the C s value of our previous study for the CS: PEO: NH 4 SCN system was 3.8 F/g at 50 mV/s [ 4 ].…”

“…However, traditional batteries deliver lower power and store adequate energy than the traditional capacitors [ 1 , 3 ]. 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 ]. Recently, 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 ].…”

The Study of the Degree of Crystallinity, Electrical Equivalent Circuit, and Dielectric Properties of Polyvinyl Alcohol (PVA)-Based Biopolymer Electrolytes

“…Herein, a promising methodology known as polymer blending has been implemented often to develop new polymeric materials with unique properties that differ from their individual components. This method is usually facile, efficient, and time-saving for synthesizing polymeric materials with desired properties [ 31 , 32 , 33 ]. Polymer blending is also easy to process, reforming polymers with high flexibility [ 34 ].…”

Characteristics of Dye-Sensitized Solar Cell Assembled from Modified Chitosan-Based Gel Polymer Electrolytes Incorporated with Potassium Iodide

“…This is attributed to the bulk resistance with the charge transfer resistance representing the diffusion resistance of electrolytes. However, the tails (i.e., spike) are obtained by adding salt, which corresponded to the blocking effect of the electrode [ 30 , 31 , 32 ]. Additionally, the bulk electrical resistance R b value for each GPE system has been determined from the complex impedance plots at the low-frequency intercept on the real axis ( Z r ).…”