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The increased interest in the transition from liquid to solid polymer electrolytes (SPEs) has driven enormous research in the area polymer electrolyte technology. Solid biopolymer electrolytes (SBEs) are a special class of SPEs that are obtained from natural polymers. Recently, SBEs have been generating much attention because they are simple, inexpensive, and environmentally friendly. In this work, SBEs based on glycerol-plasticized methylcellulose/pectin/potassium phosphate (MC/PC/K3PO4) are investigated for their potential application in an electrochemical double-layer capacitor (EDLC). The structural, electrical, thermal, dielectric, and energy moduli of the SBEs were analyzed via X-ray diffractometry (XRD), Fourier transforms infrared spectroscopy (FTIR), electrochemical impedance spectroscopy (EIS), transference number measurement (TNM), and linear sweep voltammetry (LSV). The plasticizing effect of glycerol in the MC/PC/K3PO4/glycerol system was confirmed by the change in the intensity of the samples' FTIR absorption bands. The broadening of the XRD peaks demonstrates that the amorphous component of SBEs increases with increasing glycerol concentration, while EIS plots demonstrate an increase in ionic conductivity with increasing plasticizer content owing to the formation of charge-transfer complexes and the expansion of amorphous domains in polymer electrolytes (PEs). The sample containing 50% glycerol has a maximal ionic conductivity of about 7.5 × 10−4 scm−1, a broad potential window of 3.99 V, and a cation transference number of 0.959 at room temperature. Using the cyclic voltammetry (CV) test, the EDLC constructed from the sample with the highest conductivity revealed a capacitive characteristic. At 5 mVs−1, a leaf-shaped profile with a specific capacitance of 57.14 Fg−1 was measured based on the CV data. [ABSTRACT FROM AUTHOR]

Solid polymer blend electrolyte (SPE) films of Polyethylene oxide(PEO)/Carboxymethyl cellulose (NaCMC) doped with Sodium iodide (NaI), were prepared by solution cast method and their structural, optical and electrical properties were investigated using X-Ray diffraction, Fourier transform infrared spectroscopy, UV–Vis spectrophotometer and Electrical impedance analyser respectively. X-Ray diffraction spectra indicate that, deformation occurred in the structure of the blend followed by doping with NaI salt. The variation in intensity and shifting of characteristic bands in FTIR spectra provides the evidence for formation of complex due to the interaction occurred in the blend with the dopant. Optical energy band gap decreases in the blend samples upon doping and is confirmed by UV–Vis spectrophotometer analysis. Increase of dielectric constant and loss upon doping, exhibits usual behaviour of the polymer electrolytes. An increase in AC conductivity is observed upon doping and maximum conductivity of 9.41 × 10−3 Scm−1 is obtained for 10/90 sample doped with 0.03% Sodium iodide and DC conductivity for the same sample at room temperature is 1.05 × 10–2 Scm−1. In addition, I-T studies confirm the conductivity exhibited by the sample as due to ions and I-V studies show electrochemical stability in the range of good working potential. From the results obtained, it can be inferred that, the prepared sample can be used as polymer electrolytes in the manufacturing of energy storage devices. [ABSTRACT FROM AUTHOR]

• Yttrium oxide (Y 2 O 3), zirconium dioxide (ZrO 2) and Y 2 O 3 stabilized ZrO 2 (YSZ) were prepared. • The structural, electrical, morphological, thermal and positron properties were studied. • The positron trapping rate increased for ZrO 2 /PVA polymer ceramic composite (PCC). • The carrier concentration (n) , mobility (μ) , and diffusion coefficient (D) have been calculated. • Ionic conductivity of 2.77 × 10−7 s cm−1 was recorded for ZrO 2 /PVA sample. This article presents a comparative analysis of three distinct zirconia-inserted polyvinyl alcohol (PVA) polymer matrices. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM) were used for the study of structural, chemical composition (functional groups), and morphological properties. Changes in IR bands revealed the interaction of nanofillers with the PVA matrix. ZrO 2 added sample shows the lowest degree of crystallinity with the least free volume compared to pristine PVA. Threadlike chains and scattershot crystal morphologies were seen in AFM images, and the PVA/ZrO 2 has the lowest level of roughness (1.27 nm). Positron annihilation lifetime profile showed identical behavior for τ 3 , τ 2 , and their intensities I 3 , I 2. ZrO 2 nanoparticles had a better interfacial interaction with the PVA matrix, which resulted in a higher T g and shorter o-Ps lifetime (τ 3). The positron trapping rate increased for ZrO 2 /PVA polymer ceramic composite (PCC), which indicated that both volume expansion and vacancy trapping effects occur when the positrons are effectively trapped at vacancies. The Nyquist plot for dielectric measurement was investigated, and an equivalent circuit model was used to evaluate variables such as carrier concentration (n) , mobility (μ) , and diffusion coefficient/ diffusivity (D). Ionic conductivity of 2.77 × 10−7 S cm−1 was recorded for the ZrO 2 /PVA sample. This might be due to a change (increase) in the carrier concentration. [ABSTRACT FROM AUTHOR]