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1.
Polymer blended films of polyethylene oxide (PEO)?+?polyvinyl pyrrolidone (PVP):lithium perchlorate (LiClO4) embedded with silver (Ag) nanofiller in different concentrations have been synthesized by a solution casting method. The semi-crystalline nature of these polymer films has been confirmed from their X-ray diffraction (XRD) profiles. Fourier transform infrared spectroscopy (FTIR) and Raman analysis confirmed the complex formation of the polymer with dopant ions. Dispersed Ag nanofiller size evaluation study has been done using transmission electron microscopy (TEM) analysis. It was observed that the conductivity increases when increasing the Ag nanofiller concentration. On the addition of Ag nanofiller to the polyethylene oxide (PEO)?+?polyvinyl pyrrolidone (PVP):Li+ electrolyte system, it was found to result in the enhancement of ionic conductivity. The maximum ionic conductivity has been set up to be 1.14?×?10?5 S cm?1 at the optimized concentration of 4 wt% Ag nanofiller-embedded (45 wt%) polyethylene oxide (PEO)?+?(45 wt%) polyvinyl pyrrolidone (PVP):(10 wt%) Li+ polymer electrolyte nanocomposite at room temperature. Polyethylene oxide (PEO)?+?polyvinyl pyrrolidone (PVP):Li+ +Ag nanofiller (4 wt%) cell exhibited better performance in terms of cell parameters. This is ascribed to the presence of flexible matrix and high ionic conductivity. The applicability of the present 4 wt% Ag nanofiller-dispersed polyethylene oxide (PEO)?+?polyvinyl pyrrolidone (PVP):Li+ polymer electrolyte system could be suggested as a potential candidate for solid-state battery applications. Dielectric constants and dielectric loss behaviours have been studied.  相似文献   

2.
Sodium ion conducting solid polymer blend electrolyte thin films have been prepared by using polyvinyl alcohol (PVA)/poly(vinyl pyrrolidone) (PVP) with NaNO3 by solution cast technique. The prepared films were characterized by various methods. The complexation of the salt with the polymer blend was identified by X-ray diffraction (XRD) and Fourier transforms infrared spectroscopy (FTIR), Differential scanning calorimetry was used to analyze the thermal behavior of the samples, and the glass transition temperature is low for the highest conducting polymer material. The scanning electron microscopy gives the surface morphology of the polymer electrolytes. The frequency and temperature dependent of electrical conductivities of the films were studied using impedance analyzer in the frequency range of 1 Hz to 1 MHz. The highest electrical conductivity of 50PVA/50PVP/2 wt% NaNO3 concentration has been found to be 1.25 × 10?5 S cm?1 at room temperature. The electrical permittivity of the polymer films have been studied for various temperatures. The transference number measurements showed that the charge transport is mainly due to ions than electrons. Using this highest conducting polymer electrolyte, an electrochemical cell is fabricated and the parameters of the cells are tabulated.  相似文献   

3.
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 Tg 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.  相似文献   

4.
Sodium ion conducting polymer blend electrolyte films, based on polyethylene oxide (PEO) and polyvinyl pyrrolidone (PVP) complexed with NaF salt, were prepared using solution casting technique. The complexation of the salt with the polymer blend was confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and UV-vis spectroscopy. Electrical conductivity of the films was measured with impedance analyzer in the frequency range of 1 Hz to 1 MHz and in the temperature range of 303-348 K. It was observed that the magnitude of conductivity increased with the increase in the salt concentration as well as the temperature. UV-vis absorption spectra in wavelength region of 200-800 nm were used to evaluate the optical properties like direct and indirect optical energy band gaps, optical absorption edge. The optical band gaps decreased with the increase in Na+ ion concentration. This suggests that NaF, as a dopant, is a good choice to improve the electrical properties of PEO/PVP polymer blend electrolytes.  相似文献   

5.
Structural, thermal, electrical and electrochemical behaviour of polymer blend electrolytes comprising polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) as host polymers and Mg(ClO4)2 as dopant salt have been investigated. The changes in the structural properties on the incorporation of dopant in the blends were investigated by XRD and FTIR analyses. Thermal properties of pure PVA–PVP blend and their complexes were examined by DSC to measure how the thermal transitions of the prepared films were affected by different concentration of Mg(ClO4)2. The ionic conductivity and dielectric behaviour were explored using A.C. impedance spectroscopy. The trend of ionic conductivity increases almost proportionally to the content of magnesium salt and can be related to an increase of amorphous phase at high level of dopant salt. The electrochemical stability of the optimum conducting blend polymer electrolyte is found to be ~3.5 V. The Mg2+ transference number for the sample with optimized conductivity was found to be 0.31.  相似文献   

6.
A solid polymer electrolyte (SPE) composites consisting blend of poly(ethylene oxide) (PEO) and poly(ethylene glycol) (PEG) as the polymer host with LiCF3SO3 as a Li+ cation salt and TiO2 nanoparticle which acts as a filler were prepared using solution-casting technique. The SPE films were characterized by X-ray diffraction and Fourier transform infrared analysis to ensure complexation of the polymer composites. Frequency-dependent impedance spectroscopy observation was used to determine ionic conductivity and dielectric parameters. Ionic conductivity was found to vary with increasing salt and filler particle concentrations in the polymer blend complexes. The optimum ambient temperature conductivity achieved was 2.66?×?10?4?S?cm?1 for PEO (65 %), PEG (15 %), LiCF3SO3 (15 %), ethylene carbonate (5 %), and TiO2 (3 %) using weight percentage. The dielectric relaxation time obtained from a loss tangent plot is fairly consistent with the conductivity studies. Both Arrhenius and VTF behaviors of all the composites confirm that the conductivity mechanism of the solid polymer electrolyte is thermally activated.  相似文献   

7.
This paper reports on preparation and characterization of thin films of a new zinc ion conducting blended polymer electrolyte system containing polyethylene oxide [PEO] and polypropylene glycol [PPG] complexed with zinc triflate [Zn(CF3SO3)2] salt. The room temperature ionic conductivity (σ 298K) data of such PEO-PPG polymer blends prepared by solution casting technique were found to be of the order of 10?5 S cm?1, whereas the optimized composition containing 90:10 wt% ratio of PEO and PPG possessed an appreciably high ionic conductivity of 7.5?×?10?5 S cm?1. Subsequently, six different weight percentages of zinc triflate viz., 2.5, 5, 7.5, 10, 12.5 and 15, respectively, were added into the above polymer blend and resulting polymer-salt complexes were characterized by means of various analytical tools. Interestingly, the best conducting specimen namely 87.5 wt% (PEO:PPG)-12.5 wt% Zn(CF3SO3)2 exhibited an enhanced room temperature ionic conductivity of 6.9?×?10?4 S cm?1 with an activation energy of 0.6 eV for ionic conduction. The present XRD results have indicated the occurrence of characteristic PEO peaks and effects of salt concentration on the observed intensity of these diffraction peaks. Appropriate values of degree of crystallinity for different samples were derived from both XRD and DSC analyses, while an examination of surface morphology of the blended polymer electrolyte system has revealed the formation of homogenous spherulites involving a rough surface and relevant zinc ionic transport number was found to be 0.59 at room temperature for the best conducting polymer electrolyte system thus developed.  相似文献   

8.
We report blend-based plastic polymer electrolyte (i.e., polyethylene oxide (PEO)–polydimethyl siloxane (PDMS)–lithium hexafluorophosphate (LiPF6)) with substantial improvement in DC conductivity at ambient and subambient temperatures when compared with literature reports. Conductivity variation with salt concentration, investigated within ±30 °C range, indicates an optimum conductivity of 5.6?×?10?5 S cm?1 at 30 °C for Ö/Li ~10 with a further lowering by one order at 0 °C and it remains unaltered at ?10 °C. Enhanced conductivity in this blend electrolyte, though lower than two copolymer counterparts, is attributed to very low glass transition temperatures of the host polymers. X-ray diffraction (XRD) and scanning electron microscopy (SEM) suggest an effective blending between the two polymers with an effective interaction between the Li salt and the blend polymer matrix. Raman spectroscopy results indicated that cation (Li+) coordination occurs at the C=Ö site in PEO out of the two electron-rich sites (i.e., CÖ and Si–Ö–Si) in the PEO–PDMS blend. The blend electrolytes are predominantly ionic (t ion ~97 %).  相似文献   

9.
The studies on solid polymer electrolyte (SPE) films with high ionic conductivity suitable for the realization of all solid-state Na-ion cells? form the focal theme of the work presented in this paper. The SPE films are obtained by the solution casting technique using the blend solution of poly (ethylene oxide) (PEO) with ethylene carbonate (EC) and propylene carbonate (PC) and complexed with sodium nitrate. Structural and thermal studies of SPE films are done by XRD, FTIR spectroscopy, and TGA techniques. Surface morphology of the films is studied using the FESEM. The ionic conductivity of SPE films is determined from the electrochemical impedance spectroscopy studies. For the SPE film with 16 wt% of NaNO3 used for reacting with the polymer blend of PEO with EC and PC, the ionic conductivity obtained is around 1.08 × 10?5 S cm?1. Addition of the Al2O3 as the filler material is found to enhance the ionic conductivity of the SPE films. The studies on the Al2O3 modified SPE film show an ionic conductivity of 1.86 × 10–4 S cm?1, which is one order higher than that of the SPE films without the filler content. For the SPE film dispersed with 8 wt% of Al2O3, the total ion transport number observed is around 0.9895, which is quite impressive from the perspective of the applications in electrochemical energy storage devices. From the cyclic voltammetry studies, a wide electrochemical stability window up to 4 V is observed, which further emphasizes the commendable electrochemical behavior of these SPE films.  相似文献   

10.
A biodegradable solid polymer blend electrolyte was prepared by using polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) polymers with different molecular weight percentages (wt.%) of ammonium acetate, and its structural, thermal, vibrational, and electrical properties were evaluated. The polymer blend electrolyte is prepared using solution casting technique, with water as a solvent. X-ray diffraction shows that the incorporation of ammonium acetate into the polymeric matrix causes decrease in the crystallinity degree of the samples. The Fourier transform infrared spectroscopy and laser Raman studies confirm the complex formation between the polymer and salt. Differential scanning calorimerty shows that the thermal stability of the polymer blend electrolyte and the glass transition temperature decreased as the concentration of ammonium acetate increased. The ionic conductivity of the prepared polymer electrolyte was found by AC impedance spectroscopic analysis. A maximum conductivity of 8.12?×?10?5 Scm?1 was observed for the composition of 50 PVA/50 PVP/30 wt.% of CH3COONH4.  相似文献   

11.
Poly (ethylene oxide) (PEO)/polyvinylpyrrolidone (PVP) blended nanocomposite polymers, incorporating graphene oxide (GO) nano-sheets and embedded with NaIO4 salt, were prepared using solution casting technique. The as-prepared nanocomposite electrolyte membranes were characterized by SEM, TEM, XRD, and Raman vibrational spectroscopic techniques to confirm the dispersion of GO nano-sheets and to understand the synergistic properties of GO/polymer interactions as a function of GO nano-sheets concentration. GO fillers incorporated electrolyte membranes demonstrated distinctive surface morphology composed of circular-shaped protuberances of different dimensions. The decrease of Raman intensity ratio (ID/IG) and in-plane crystallite size (La) values of the nanocomposites suggested the good dispersion and confinement of the GO nano-sheets. The optical properties of blend electrolyte films were studied as a function of GO filler concentration using optical absorption and diffuse reflectance spectra. In reference to PEO/PVP/NaIO4, the resultant PEO/PVP/NaIO4/GO (0.4% in weight) electrolyte membrane demonstrated both an increase in tensile strength of ca. 42% and in Young’s modulus of ca. 40%, improvements coupled with a maximum fractured elongation of 3%. Through impedance spectroscopy analysis, the role of the GO nano-sheets onto the room temperature conductivity properties of the prepared electrolyte membranes has been probed.  相似文献   

12.
Solid polymer electrolytes (SPEs) based on poly (vinyl chloride)/poly (ethyl methacrylate) [PVC/PEMA] blend complexed with zinc triflate [Zn(CF3SO3)2] salt have been prepared using solution casting technique. Thin film samples containing various blend ratios of PVC/PEMA with fixed composition of salt have been examined by means of complex impedance analysis, and as a consequence, the typical composition corresponding to PVC (30 wt%)/PEMA (70 wt%) has been identified as the optimized blend exhibiting the highest room temperature ionic conductivity of 10?8 Scm?1. The ionic conductivity of the optimized blend was further enhanced from 10?8 to 10?6 Scm?1 by adding the chosen salt in different weight percentages at 301 K. The occurrence of complexation of the polymer blend and an evidence of interaction of cations, namely Zn2+ ions with the polymer blend, have been confirmed by Attenuated total reflectance-Fourier transformed infrared (ATR-FTIR) spectroscopy measurement studies. The efficacy of ion-polymer interactions was estimated by means of an evaluation of transport number data pertaining to Zn2+ ions which was found to be 0.56. The apparent changes resulting in the structural properties of these polymer electrolytes possessing a honeycomb-like microporous structure were identified using X-ray diffraction (XRD) and scanning electron microscopic (SEM) studies. Such promising features of the present polymer blend electrolyte system appear to suggest possible fabrication of new rechargeable zinc batteries involving improved device characteristics.  相似文献   

13.
Sodium-ion-conducting poly(ethylene oxide) (PEO)-based solid polymer electrolyte films mixed with salt sodium thiocyanate (NaSCN) have been prepared by solution-cast method. Films were characterized in detail using optical microscopy, differential scanning calorimetry, and impedance spectroscopy. The drop in ionic conductivity with increasing salt concentration is supported by a decrease in number of charge carriers. Dielectric constant is supported by decreases in numbers of charge carriers and increase in mobility. The maximum ionic conductivity and number of charge carriers for material are found 9.86 × 10?6 S/m and 1.21 × 1020, respectively, for weight % ratio (95:05) of PEO:NaSCN polymer salt complex. The maximum mobility of material is found 2.58 × 10?6 m2/Vs for weight % ratio (80:20) of PEO:NaSCN polymer salt complex.  相似文献   

14.
Proton-conducting solid polymer blend electrolytes based on methylcellulose-polyvinyl alcohol:ammonium nitrate (MC-PVA:NH4NO3) were prepared by the solution cast technique. The structural and electrical properties of the samples were examined by X-ray diffraction (XRD), Fourier transform infrared (FTIR), and electrical impedance (EI) spectroscopy. The shifting and change in the intensity of FTIR bands of the electrolyte samples confirm the complex formation between the MC-PVA polymer blend and the NH4NO3 added salt. The observed broadening in the XRD pattern of the doped samples reveals the increase of the amorphous fraction of polymer electrolyte samples. The increase in electrical conductivity of polymer electrolyte samples with increasing salt concentration attributed to the formation of charge-transfer complexes, and to increase in the amorphous domains. A maximum ionic conductivity of about 7.39 × 10?5 S cm?1 was achieved at room temperature for the sample incorporating 20 wt% of NH4NO3. The DC conductivity of the present polymer system exhibits Arrhenius-type dependence with temperature. The decrease in the values of activation energies with increasing salt concentration indicates the ease mobility of ions. The decrease in dielectric constant with increasing frequency was observed at all temperatures. Optical properties such as absorption edge, optical band gap, and tail of localized state were estimated for polymer blend and their electrolyte films. It was found that the optical band gap values shifted towards lower photon energy from 6.06 to 4.75 eV by altering the NH4NO3 salt content.  相似文献   

15.
A series of solid polymer electrolytes (SPEs) based on poly (ethylene oxide)/polylactic acid (PEO/PLA) with liquid crystal ionomer (LCI) intercalated montmorillonite (MMT) nanocomposites (LCI-MMT) has been prepared by solution blending method. The effects of LCI-MMT on the structural, crystallization, thermal, and ionic conductivity properties of solid polymer electrolytes have been analyzed. It is demonstrated that the incorporation of LCI-MMT into the blend suppressed the crystallinity of PEO and increased the crystallinity of PLA. The maximum ionic conductivity is found to be in the range of 1.05?×?10?5 S/cm for 0.5 wt% LCI-MMT, which is higher than that of the LCI-MMT-free polymer electrolyte (5.36?×?10?6 S/cm) at room temperature.  相似文献   

16.
Biodegradable polymer electrolyte comprising the blend of chitosan (CS) and poly(ethylene glycol) (PEG) plasticized with ethylene carbonate and propylene carbonate, as host polymer, and lithium perchlorate (LiClO4), as a dopant, was prepared by solution casting technique. The ionic conductivity has been calculated using the bulk impedance obtained through impedance spectroscopy. The variation of conductivity and dielectric properties has been investigated as a function of polymer blend ratio, plasticizer content and LiClO4 concentration at temperature range of 298–343 K. The DSC thermograms show two broad peaks for CS/PEG blend and increased with increase in the LiClO4 content. The maximum conductivity has been found to be 1.1?×?10?4 S cm?1 at room temperature for 70:30 (CS/PEG) concentration. The electric modulus of the electrolyte film exhibits a long tail feature indicative of good capacitance. The activation energy of all samples was calculated using the Arrhenius plot, and it has been found to be 0.12 to 0.38 eV. A carbon–carbon supercapacitor has been fabricated using this electrolyte, and its electrochemical characteristics and performance have been studied. The supercapacitor showed a fairly good specific capacitance of 47 F?g?1.  相似文献   

17.
Solid polymer electrolytes based on high molecular weight poly(ethylene oxide) (PEO) complexed with lithium difluoro(oxalato)borate (LiDFOB) salt in various EO:Li molar ratios from 30:1 to 8:1 were prepared by using solution casting technique. Ion–polymer interaction, structural, thermal, and ionic conductivity studies have been reported by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), polarized optical microscopy (POM), differential scanning calorimeter (DSC), and impedance analysis. FTIR spectral studies suggested that the interaction of Li+ cations with the ether oxygen of PEO, where a triple peak broad band centered at 1105 cm?1, corresponds to C–O–C stretching and extreme deformation occurs. XRD, POM, and DSC indicated that the inclusion of LiDFOB salt could reduce the crystallinity of PEO. The melting temperature of PEO shifted to lower temperature side by the addition of LiDFOB. The glass transition temperature obtained for the system 10:1 was ?38.2 °C. An increase in the ionic conductivity from 3.95?×?10?9 to 3.18?×?10?5 S/cm at room temperature (23 °C) was obtained through the addition of LiDFOB to a high molecular weight PEO. In addition, the ionic conductivity of the polymer electrolyte films followed an Arrhenius relation, and the activation energy decreased with increasing LiDFOB concentration.  相似文献   

18.
A series of conducting thin-film solid electrolytes based on poly (vinyl alcohol)/ poly (vinyl pyrrolidone) (PVA/PVP) polymer blend was prepared by the solution casting technique. PVA and PVP were mixed in various weight percent ratios and dissolved in 20 ml of distilled water. The samples were analyzed by using impedance spectroscopy in the frequency range between 100 Hz and 1 MHz. The PVA/PVP system with a composition of 80% PVA and 20 wt.% PVP exhibits the highest conductivity of (2.2±1.4) × 10−7 Scm−1. The highest conducting PVA/PVP blend was then further studied by adding different amounts of potassium hydroxide (KOH) ionic dopant. Water has been used as solvent to prepare PVA/PVP-KOH based alkaline solid polymer blend electrolyte films. The conductivity was enhanced to (1.5 ± 1.1) × 10−4 Scm−1 when 40 wt.% KOH was added. Paper presented at the International Conference on Functional Materials and Devices 2005, Kuala Lumpur, Malaysia, June 6 – 8, 2005.  相似文献   

19.
A solid polymer electrolytes (SPE) comprising blend of poly(ethylene oxide; PEO) and epoxidized natural rubber as a polymer host and LiCF3SO3 as a dopant were prepared by solution-casting technique. The SPE films were characterized by field emission scanning electron microscopy to determine the surface morphology, X-ray diffraction, and differential scanning calorimeter to determine the crystallinity and thermogravimetric analysis to confirm the mass decrease caused by loss of the solvent. While the presence of the complexes was investigated by reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Electrochemical impedance spectroscopy was conducted to obtain ionic conductivity. Scanning electron microscopy analysis showed that a rough surface morphology of SPE became smoother with addition of salt, while ATR-FTIR spectroscopy analysis confirmed the polymer salt complex formation. The interaction occurred between the salt, and ether group of polymer host where the triple peaks of ether group in PEO merged and formed one strong peak at 1,096 cm−1. Ionic conductivity was found to increase with the increase of salt concentration in the polymer blend complexes. The highest conductivity achieved was 1.4 × 10−4 Scm−1 at 20 wt.% of LiCF3SO3, and this composition exhibited an Arrhenius-like behavior with the activation energy of 0.42 eV and the preexponential factor of 1.6 × 103 Scm−1.  相似文献   

20.
Lithium ion-conducting membranes with poly(ethylene oxide) (PEO)/poly(vinylidene chloride-co-acrylonitrile) (PVdC-co-AN)/lithium perchlorate (LiClO4) were prepared by solution casting method. Different plasticizers ethylene carbonate (EC), propylene carbonate (PC), gamma butyrolactone (gBL), diethyl carbonate (DEC), dimethyl carbonate (DMC), and dibutyl phthalate (DBP) were complexed with the fixed ratio of PEO/PVdC-co-AN/LiClO4. The preparation and physical and electrochemical properties of the gel polymer electrolytes have been briefly elucidated in this paper. The maximum ionic conductivity value computed from the ac impedance spectroscopy is found to be 3?×?10?4 S cm?1 for the EC-based system. From DBP-based system down to EC-based system, a decrease of crystallinity and an increase of amorphousity are depicted by X-ray diffraction technique, the decrease of band gap energy is picturized through UV–visible analysis, the decrease of glass transition temperature is perceived from differential scanning calorimetry plots, and the reduction of photoluminescence intensity is described through photoluminescence spectroscopy study at an excitation wavelength of 280 nm. Atomic force microscopic images of EC-based polymer electrolyte film show the escalation of micropores. Fourier transform infrared spectroscopy study supports the complex formation and the interaction between the polymers, salt, and plasticizer. The maximum thermal stability is obtained from thermogravimetry/differential thermal analysis, which is found to be 222 °C for the sample complexed with EC. The cyclic voltagram of the sample having a maximum ionic conductivity shows a small redox current at the anode, and cathode and the chemical stability is confirmed by linear sweep voltammetry.  相似文献   

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