NH<Subscript>4</Subscript>NO<Subscript>3</Subscript> as charge carrier contributor in glycerolized potato starch-methyl cellulose blend-based polymer electrolyte and the application in electrochemical double-layer capacitor

Potato starch (PS)-methyl cellulose (MC) blend solid biopolymer electrolytes infused with ammonium nitrate (NH₄NO₃) and glycerol as plasticizer are made via the solution cast technique. Fourier transform infrared (FTIR) spectroscopy indicates that NH₄NO₃ has interacted with the polymer blend host. The addition of 40 wt% glycerol in the highest conducting plasticizer free electrolyte has improved the conductivity to the order of ～10^?3 S cm^?1. The thermal stability of the electrolytes is identified by thermogravimetric analysis (TGA). Result from X-ray diffraction (XRD) analysis shows that the electrolyte with maximum conductivity value has the lowest degree of crystallinity. Differential scanning calorimetry (DSC) analysis reveals that the highest conducting plasticized electrolyte possesses the lowest glass transition temperature (T _g) of ?27.5 °C. Conductivity trend is further verified by dielectric analysis. Transference numbers of ion (t _ion) and electron (t _e) for the highest conducting electrolyte are identified to be 0.98 and 0.02, respectively, confirming that ions are the dominant charge carriers. Linear sweep voltammetry (LSV) evaluates that the potential window for the electrolyte is 1.88 V. The internal resistance of the electrochemical double-layer capacitor (EDLC) is between 29 and 64 Ω. From the charged-discharged measurement, the value of C _s is 31 F g^?1. The EDLC is stable over 1000 cycles.     

The effect of NH<Subscript>4</Subscript>NO<Subscript>3</Subscript> towards the conductivity enhancement and electrical behavior in methyl cellulose-starch blend based ionic conductors

Solid polymer electrolytes based on methyl cellulose (MC)-potato starch (PS) blend doped with ammonium nitrate (NH₄NO₃) are prepared by solution cast technique. The interaction between the electrolyte’s materials is proven by Fourier transform infrared (FTIR) analysis. The thermal stability of the electrolytes is obtained from thermogravimetric analysis (TGA). The room temperature conductivity of undoped 60 wt.% MC-40 wt.% PS blend film is identified to be (1.04 ± 0.19) × 10^?11 S cm^?1. The addition of 30 wt.% NH₄NO₃ to the polymer blend has optimized the room temperature conductivity to (4.37 ± 0.16) × 10^?5 S cm^?1. Conductivity trend is verified by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and dielectric analysis. Temperature-dependence of conductivity obeys Arrhenius rule. Conductivity is found to be influenced by the number density (n) and mobility (μ) of ions. From transference number measurements (TNM), ions are found to be the dominant charge carriers.     

Green electrolytes based on dextran-chitosan blend and the effect of NH<Subscript>4</Subscript>SCN as proton provider on the electrical response studies

Dextran-chitosan blend added with ammonium thiocyanate (NH₄SCN)-based solid polymer electrolytes are prepared by solution cast method. The interaction between the components of the electrolyte is verified by Fourier transform infrared (FTIR) analysis. The blend of 40 wt% dextran-60 wt% chitosan is found to be the most amorphous ratio. The room temperature conductivity of undoped 40 wt% dextran-60 wt% chitosan blend film is identified to be (3.84?±?0.97)?×?10^?10 S cm^?1. The inclusion of 40 wt.% NH₄SCN to the polymer blend has optimized the room temperature conductivity up (1.28?±?0.43)?×?10^?4 S cm^?1. Result from X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis shows that the electrolyte with the highest conductivity value has the lowest degree of crystallinity (χ _c) and the glass transition temperature (T _g), respectively. Temperature-dependence of conductivity follows Arrhenius theory. From transport analysis, the conductivity is noticed to be influenced by the mobility (μ) and number density (n) of ions. Conductivity trend is further verified by field emission scanning electron microscopy (FESEM) and dielectric results.     

Effect of ethylene carbonate plasticizer on agar-agar: NH<Subscript>4</Subscript>Br-based solid polymer electrolytes

Proton-conducting polymer electrolytes based on biopolymer, agar-agar as the polymer host, ammonium bromide (NH₄Br) as the salt and ethylene carbonate (EC) as the plasticizer have been prepared by solution casting technique with dimethylformamide as solvent. Addition of NH₄Br and EC with the biopolymer resulted in an increase in the ionic conductivity of polymer electrolyte. EC was added to increase the degree of salt dissociation and also ionic mobility. The highest ionic conductivity achieved at room temperature was for 50 wt% agar/50 wt% NH₄Br/0.3% EC with the conductivity 3.73?×?10^?4 S cm^?1. The conductivity of the polymer electrolyte increases with the increase in amount of plasticizer. The frequency-dependent conductivity, dielectric permittivity (ε′) and modulus (M′) studies were carried out.     

The effect of LiCF<Subscript>3</Subscript>SO<Subscript>3</Subscript> on the complexation with potato starch-chitosan blend polymer electrolytes

This work examines the effect of lithium trifluoromethanesulfonate (LiCF₃SO₃) and glycerol on the conductivity and dielectric properties of potato starch-chitosan blend-based electrolytes. The electrolytes are prepared via solution cast technique. From X-ray diffraction (XRD) analysis, the blend of 50 wt.% starch and 50 wt.% chitosan is found to be the most amorphous blend. Fourier transform infrared (FTIR) spectroscopy studies show the interaction between the electrolyte materials. The room temperature conductivity of pure starch-chitosan film is found to be (2.85 ± 1.31) × 10^?10 S cm^?1. The incorporation of 45 wt.% LiCF₃SO₃ increases the conductivity to (7.65 ± 2.27) × 10^?5 S cm^?1. Further conductivity enhancement up to (1.32 ± 0.35) × 10^?3 S cm^?1 has been observed on addition of 30 wt.% glycerol. This trend in conductivity is verified by XRD and dielectric analysis. The temperature dependence of conductivity of all electrolytes are Arrhenian.     

Preparation and characterization of blend polymer electrolyte film based on poly(vinyl alcohol)-poly(acrylonitrile)/MgCl<Subscript>2</Subscript> for energy storage devices

The development of magnesium electrolytes for battery applications has been the demand for electrochemical devices. To meet such demand, in this work solid blend polymer electrolytes were prepared using polyvinyl alcohol (PVA) and polyacrylonitrile (PAN) (92.5PVA:7.5PAN) as host polymer, magnesium chloride (MgCl₂) of different molar mass percentage (m.m.%) (0.1, 0.2, 0.3, 0.4, 0.5, and 0.6%) as salt and dimethylformamide (DMF) as solvent. Structural, vibrational, thermal, electrical, and electrochemical properties of the prepared electrolytes were investigated using different techniques such as X-ray diffraction pattern, FTIR spectroscopy analysis, differential scanning calorimetry (DSC), AC impedance measurement, and transference number measurement. X-ray diffraction studies confirm the minimum volume fraction of crystalline phase for the polymer electrolyte with 0.5 m.m.% of MgCl₂. FTIR confirms the complex formation between host polymer and salt. DSC analysis proves the thermal transition of the prepared films are affected by salt concentration. The optimized material with 0.5 m.m.% of MgCl₂ offers a maximum electrical conductivity of 1.01 × 10^?3 S cm^?1 at room temperature. The Mg²⁺ ion conduction in the blend polymer electrolyte is confirmed from transference number measurement. Electrochemical analysis demonstrates the promising characteristic of these polymer films suitable as electrolytes for primary magnesium batteries. Output potential and discharge characteristics have been analyzed for primary magnesium battery which is constructed using optimized conducting electrolyte.     

Proton-conducting polymer electrolyte based on PVA-PAN blend doped with ammonium thiocyanate

Blending of polymers is one of the most useful methods for modulating the conductivity of solid polymer electrolytes. Blend polymer electrolytes have been prepared with polyvinyl alcohol (PVA)-polyacrylonitrile (PAN) blend doped with ammonium thiocyanate with different concentrations by solution casting technique, using dimethyl formamide (DMF) as the solvent. The prepared electrolytes are characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), nuclear magnetic resonance (NMR), ultraviolet (UV), and ac impedance measurement techniques. The increase in amorphous nature of the blend polymer electrolyte by the addition of salt is confirmed by XRD analysis. The complex formation between the polymers and the salt has been confirmed by FTIR analysis. The thermal behavior has been examined using DSC and TGA. The maximum conductivity has been found to be 2.4?×?10^?3 S cm^?1 for 92.5PVA/7.5PAN/25 % NH₄SCN sample at room temperature. The temperature dependence of conductivity has been studied with the help of Arrhenius plot, and the activation energies are calculated. The proton conductivity is confirmed by dc polarization measurement technique. ¹H NMR studies reveal the presence of protons in the sample. A proton battery is constructed with the highest conducting sample, and its open circuit voltage is measured to be 1.2 V     

Characterization of blend polymer PVA-PVP complexed with ammonium thiocyanate

Thin films of blend polymer electrolytes comprising poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) complexed with ammonium thiocyanate (NH₄SCN) salt in different compositions have been prepared by solution casting technique using distilled water as solvent. The prepared films have been investigated by different experimental techniques. The complexation of these films has been studied by FTIR spectroscopy. The increase in amorphousness of the films with increase in NH₄SCN content has been confirmed by XRD analysis. The addition of ammonium thiocyanate salt to PVA-PVP polymer blend shows a shift in T_g of the blend. The effect of salt concentration and temperature on the ionic conductivity of the polymer blend films has been analyzed using AC impedance spectroscopy. The maximum conductivity of 6.85 × 10^?4 S cm^?1 at room temperature has been observed for the blend with 50 mol% PVA-50 mol% PVP complexed with 40 mol% NH₄SCN. The activation energy has been found to be minimum (0.24 eV) for this sample. Wagner’s polarization technique shows that the charge transport in these blend films is predominantly due to ions. Using the highest conductivity blend polymer electrolyte, a proton battery has been fabricated and its discharge characteristics have been studied.     

Electrochemical and structural properties of a polymer electrolyte system based on the effect of CeO<Subscript>2</Subscript> nanofiller with PVDF-co-HFP for energy storage devices

In the present work, a series of five different nanocomposite polymer electrolytes (NCPEs) have been reported with varying contents of ceria, CeO₂ nanofiller suitably incorporated within an optimized composition having 75:25 wt% ratio of poly(vinylidenefluoride-co-hexafluoropropylene) [(PVDF-co-HFP)] and zinc trifluoromethanesulfonate (ZnTf) in the form of films obtained by mean of solution casting technique with a general formula [75 wt% PVDF-co-HFP:25 wt% ZnTf]-x wt% CeO₂ where x = 1, 3, 5, 7, and 10, respectively. The chosen NCPE system is found to exhibit the maximum electrical conductivity of 3 × 10^?4 S cm^?1 for 5 wt% loading of CeO₂ nanofiller at ambient temperature. The observed conductivity enhancement has been attributed to the occurrence of an increase in the amorphous content as confirmed by X-ray diffraction (XRD) analysis. Detailed Fourier transform infrared (FTIR) spectral analysis has indicated the feasibility of complexation of the host polymer matrix with ZnTf salt and CeO₂ nanofiller. The incorporation of CeO₂ nanofiller has further increased the decomposition voltage of the polymer electrolyte from 2.4 to 2.7 V as revealed from the voltammetric studies performed on such NCPEs, thereby suggesting the suitability of these NCPE films with an enhanced electrical conductivity as new electrolytes in order to design and fabricate eco-friendly zinc rechargeable batteries and other electrochemical devices.     

Effect of ZnO nanoparticles filler concentration on the properties of PEO-ENR50-LiCF<Subscript>3</Subscript>SO<Subscript>3</Subscript> solid polymeric electrolyte

A solid polymer electrolyte comprising blend of poly(ethylene oxide) and 50% epoxidized natural rubber (ENR50) as a polymer host, LiCF₃SO₃ as a salt and nanoparticle ZnO as an inorganic filler was prepared by solution-casting technique. The effect of filler on the electrolyte properties was characterized and analysed. FESEM analysis showed that the filler was well distributed in the polymer matrix, while the effective interaction between the salt and the polymer host was reduced by the addition of filler. As evidenced by FTIR analysis, which showed the formation of triplet peak at C-O-C stretching region. Ionic conductivity was found to decrease from 1.4 × 10⁻⁴ Scm⁻¹ to 2.5 × 10⁻⁶ Scm⁻¹ upon the addition of filler, due to the blocking effect of filler into the electrolyte conduction pathways. The temperature dependence on the electrolyte conductivity obeys Arrhenius rule in two temperature regions.     

The development of Li<Superscript>+</Superscript> conducting polymer electrolyte based on potato starch/graphene oxide blend

Solid polymer electrolytes based on potato starch (PS) and graphene oxide (GO) have been developed in this study. Blending GO with PS has improved the ionic conductivity and mechanical properties of the electrolytes. In this work, series of polymer blend consisting of PS and GO as co-host polymer were prepared using solution cast method. The most amorphous PS-GO blend was obtained using 80 wt% of PS and 20 wt% of GO as recorded by X-ray diffraction (XRD). Incorporation of 40 wt% lithium trifluoromethanesulfonate (LiCF₃SO₃) into the PS-GO blend increases the conductivity to (1.48 ± 0.35) × 10^?5 S cm^?1. Further enhancement of conductivity was made using 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]). The highest conductivity at room temperature is obtained for the electrolyte containing 30 wt% of [Bmim][Cl] with conductivity value of (4.8?0 ± 0.69) × 10^?4 S cm^?1. Analysis of the Fourier transform infrared spectroscopy (FTIR) spectra confirmed the interaction between LiCF₃SO₃, [Bmim][Cl], and PS-GO blend. The variation of the dielectric constant and modulus studies versus frequency indicates that system of PS-GO-LiCF₃SO₃-[Bmim][Cl] obeys non-Debye behavior.     

Structural and electrical properties of pure and H<Subscript>2</Subscript>SO<Subscript>4</Subscript> doped (PVA)<Subscript>0.7</Subscript>(NaI)<Subscript>0.3</Subscript> solid polymer electrolyte

Solid polymer electrolytes (SPE) based on poly-(vinyl alcohol) (PVA)_0.7 and sodium iodide (NaI)_0.3 complexed with sulfuric acid (SA) at different concentrations were prepared using solution casting technique. The structural properties of these electrolyte films were examined by X-ray diffraction (XRD) studies. The XRD data revealed that sulfuric acid disrupt the semi-crystalline nature of (PVA)_0.7(NaI)_0.3 and convert it into an amorphous phase. The proton conductivity and impedance of the electrolyte were studied with changing sulfuric acid concentration from 0 to 5.1 mol/liter (M). The highest conductivity of (PVA)_0.7(NaI)_0.3 matrix at room temperature was 10⁻⁵ S cm⁻¹ and this increased to 10⁻³ S cm⁻¹ with doping by 5.1 M sulfuric acid. The electrical conductivity (σ) and dielectric permittivity (ε′) of the solid polymer electrolyte in frequency range (500 Hz–1 MHz) and temperature range (300–400) K were carried out. The electrolyte with the highest electrical conductivity was used in the fabrication of a sodium battery with the configuration Na/SPE/MnO₂. The fabricated cells give open circuit voltage of 3.34 V and have an internal resistance of 4.5 kΩ.     

Effects of various LiPF<Subscript>6</Subscript> salt concentrations on PEO-based solid polymer electrolytes

In this research, various weight percents of LiPF₆ are incorporated into PEO-based polymer electrolyte system. Thin film electrolytes are prepared via solution casting technique and characterized by FTIR, XRD and DSC analyses in order to study their complex behaviour. The amorphicity of the electrolytes are measured by DC impedance. The results reveal that the conductivity increases with increasing temperature when the salt concentration increases to 20 wt.%. The conductivity for 20 wt.% of salt remains similar to the conductivity of 15 wt.% of salt at 318 K. Impedance studies show that the conductivity increases with increasing LiPF₆ concentration, whereas XRD studies reveal that the phase changes from crystalline to amorphous when LiPF₆ concentration increases. DSC studies indicate a decrease in T _m with increasing LiPF₆ concentration. Finally, the complexation process is examined using FTIR.     

Biopolymeric electrolyte based on glycerolized methyl cellulose with NH<Subscript>4</Subscript>Br as proton source and potential application in EDLC

In the present work, biopolymer electrolyte films based on MC doped with NH₄Br salt and plasticized with glycerol were prepared by solution casting method. Fourier transform infrared (FTIR) spectroscopy analysis confirms the interaction between MC, NH₄Br, and glycerol. X-ray diffraction (XRD) explains that the enhancement of conductivity is affected by the degree of crystallinity. This result is verified by field emission scanning electron microscopy (FESEM). For unplasticized system, sample containing 25 wt% of NH₄Br possesses the highest ionic conductivity of (1.89 ± 0.05) × 10^?4 S cm^?1. The addition of 30 wt% glycerol increases the conductivity value up to (1.67 ± 0.04) × 10^?3 S cm^?1. The conduction mechanism was best presented by the correlated barrier hopping (CBH) model. The linear sweep voltammetry (LSV) and cyclic voltammetry (CV) result confirms the suitability of the highest conducting electrolyte to be employed in the fabrication of electrochemical double layer capacitor (EDLC).     

Study on the effect of PEG in ionic transport for CMC-NH<Subscript>4</Subscript>Br-based solid polymer electrolyte

The present study investigates the ion transport properties and structural analysis of plasticized solid polymer electrolytes (SPEs) based on carboxymethyl cellulose (CMC)-NH₄Br-PEG. The SPE system was successfully prepared via solution casting and has been characterized by using electrical impedance spectroscopy (EIS), Fourier transform infrared (FTIR) spectroscopy, and x-ray diffraction (XRD) technique. The highest conductivity of the SPE system at ambient temperature (303 K) was found to be 1.12?×?10^?4 S/cm for un-plasticized sample and 2.48?×?10^?3 S cm^?1 when the sample is plasticized with 8 wt% PEG. Based on FTIR analysis, it shows that interaction had occurred at O–H, C=O, and C–O moiety from CMC when PEG content was added. The ionic conductivity tabulation of SPE system was found to be influenced by transport properties and amorphous characteristics as revealed by IR deconvolution method and XRD analysis.     

Characterization of high ionic conducting PVAc–PMMA blend-based polymer electrolyte for electrochemical applications

A solid polymer blend electrolyte is prepared using poly(vinyl acetate) (PVAc) and poly(methyl methacrylate) (PMMA) polymers with different molecular weight percentage (wt%) of ammonium thiocyanate (NH₄SCN) by solution casting technique with tetrahydrofuran (THF) as a solvent. The structural, morphological, vibrational, thermal and electrical properties of the prepared polymer blend electrolytes have been studied. The incorporation of NH₄SCN into the polymeric matrix causes decrease in the degree of crystallinity of the samples. The complex formation between the polymer and salt has been confirmed by FTIR technique. The increase in T _g with increase in salt concentration has been investigated. The maximum conductivity of 3.684?×?10^?3 S cm^?1 has been observed for the composition of 70PVAc/30PMMA/30 wt% of NH₄SCN at 303 K. This value of ionic conductivity is five orders of magnitude greater than that of 70PVAc/30PMMA polymer membrane. Dielectric and transport studies have been done. The highest conducting polymer electrolyte is used to fabricate proton battery with the configuration Zn/ZnSO₄·7H₂O (anode) ||polymer electrolyte||PbO₂/V₂O₅ (cathode). The open circuit voltage of the fabricated battery is 1.83 V, and its performance has been studied.     

Effect of Al<Subscript>2</Subscript>O<Subscript>3</Subscript> nanofiller on the electrical,thermal and structural properties of PEO:PPG based nanocomposite polymer electrolyte

A new series of nanocomposite polymer electrolyte (NCPE) system comprising of polyethylene oxide (PEO) and polypropylene glycol (PPG) as blended polymer host, zinc trifluoromethanesulfonate [Zn(CF₃SO₃)₂] as dopant salt and nanocrystalline alumina [Al₂O₃] as filler was prepared by solution casting technique. The present system consisting of five different compositions of 87.5 wt% (PEO:PPG)–12.5 wt% Zn(CF₃SO₃)₂ + x wt% Al₂O₃ [where x = 1, 3, 5, 7 and 9, respectively] has been thoroughly characterized by various analytical techniques such as electrical impedance spectroscopy, X-ray diffraction (XRD) studies, differential scanning calorimetry (DSC), scanning electron microscopic (SEM) analysis and linear sweep voltammetry (LSV). The maximum room temperature ionic conductivity exhibited by the NCPE was found to be 2.1 × 10^?4 S cm^?1 for 3 wt% loading of Al₂O₃ which is an order higher than that of the optimized filler-free zinc salt doped polymer electrolyte system at 298 K. The evidence of a decrease in the degree of crystallinity responsible for the enhanced conductivity was revealed by the XRD data and further confirmed by DSC and SEM results. Moreover, the electrochemical stability window of the highly conducting electrolyte matrix has been experimentally determined by linear sweep voltammetry and found to be 3.6 V which is fairly adequate for the construction of zinc primary batteries as well as zinc-based rechargeable batteries at ambient conditions.     

Incorporation of NH4Br in PVA-chitosan blend-based polymer electrolyte and its effect on the conductivity and other electrical properties

Polymer electrolyte system based on poly(vinyl alcohol) (PVA)-chitosan blend doped with ammonium bromide (NH₄Br) has been prepared by solution cast method. Fourier transform infrared (FTIR) spectroscopy analysis confirms the complexation between salt and polymer host. The highest ionic conductivity obtained at room temperature is (7.68?±?1.24)?×?10^?4 S cm^?1 for the sample comprising of 30 wt% NH₄Br. X-ray diffraction (XRD) patterns reveal that PVA-chitosan with 30 wt% NH₄Br exhibits the most amorphous structure. Thermogravimetric analysis (TGA) reveals that the electrolytes are stable until ～260 °C. The conductivity variation can also be explained by field emission scanning electron microscopy (FESEM) study. Dielectric properties of the electrolytes follow non-Debye behavior. The conduction mechanism of the highest conducting electrolyte can be represented by the correlated barrier hopping (CBH) model. From linear sweep voltammetry (LSV) result, the highest conducting electrolyte is electrochemically stable at 1.57 V.     

Structural,thermal and ion transport studies on nanocomposite polymer electrolyte-{(PEO + SiO<Subscript>2</Subscript>):NH<Subscript>4</Subscript>SCN} system

Development and characterisation of polyethylene oxide (PEO)-based nanocomposite polymer electrolytes comprising of (PEO-SiO₂): NH₄SCN is reported. For synthesis of the said electrolyte, polyethylene oxide has been taken as polymer host and NH₄SCN as an ionic charge supplier. Sol–gel-derived silica powder of nano dimension has been used as ceramic filler for development of nanocomposite electrolytes. The maximum conductivity of electrolyte ∼2.0 × 10⁻⁶ S/cm is observed for samples containing 30 wt.% silica. The temperature dependence of conductivity seems to follow an Arrhenius-type, thermally activated process over a limited temperature range.     

The effect of composition,electron irradiation and quenching on ionic conductivity in a new solid polymer electrolyte: (PEG)<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>NH<Subscript>4</Subscript>I

We have prepared, characterized and investigated a new PEG-2000 based solid polymer electrolyte (PEG) _x NH₄I. Ionic conductivity measurements have been made as a function of salt concentration as well as temperature in the range 265–330 K. Selected compositions of the electrolyte were exposed to a beam of 8 MeV electrons to an accumulated dose of 10 kGy to study the effect on ionic conductivity. The electrolyte samples were also quenched at liquid nitrogen temperature and conductivity measurements were made. The ionic conductivity at room temperature exhibits a characteristic double peak for the composition x = 20 and 70. Both electron beam irradiation and quenching at low temperature have resulted in an increase in conductivity by 1–2 orders of magnitude. The enhancement of conductivity upon irradiation and quenching is interpreted as due to an increase in amorphous region and decrease in crystallinity of the electrolyte. DSC and proton NMR measurements also support this conclusion.