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1.
A sequence of novel plasticized polymer nanocomposite electrolyte systems based on polyethylene oxide (PEO) as polymer host, LiCF 3SO 3 as salt, and a variety of concentrations of nanochitosan as inert filler, succinonitrile as a solid non-ionic plasticizer has been prepared. The prepared membranes were subjected to X-ray diffraction, FT-IR, tensile strength, morphological studies, thermal analysis, AC ionic conductivity measurement, and interfacial analyses. The combined effect of succinonitrile and nanochitosan on the electrochemical properties of polymer electrolytes has been studied, and it was confirmed that the ionic conductivity is significantly increased. The maximum ionic conductivity of the plasticized nanocomposite polymer electrolytes are found to be in the range of 10 ?2.8?S/cm. Besides, the interfacial stability also shows a significant improvement. The tensile measurement and thermal analysis results illustrate that the electrolytes based on that polymer host possess good mechanical and thermal stabilities. 相似文献
2.
Composite polymer electrolyte systems composed of poly(methyl methacrylate) (PMMA) as the host polymer, lithium trifluoromethanesulphonate
(also known as lithium triflate; LiCF 3SO 3) as dopant salt, and a variety of different concentrations of nano-sized fumed silica (SiO 2) as inorganic filler were studied. The effect upon addition of SiO 2 on the ionic conductivity of the composite polymer electrolytes was investigated, and it was proven that the ionic conductivity
had been enhanced. In addition, the interfacial stability also showed improvement. Maximum conductivity was obtained upon
addition of 2 wt.% SiO 2. The complexation of PMMA and LiCF 3SO 3 was verified through Fourier transform infrared studies. The thermal stability of the polymer electrolytes was also found
to improve after dispersion of inorganic filler. This was proven in the thermogravimetric studies. 相似文献
3.
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 (LiCF 3SO 3) 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 LiCF 3SO 3, [Bmim][Cl], and PS-GO blend. The variation of the dielectric constant and modulus studies versus frequency indicates that system of PS-GO-LiCF 3SO 3-[Bmim][Cl] obeys non-Debye behavior. 相似文献
4.
Solid polymer electrolytes consisted of poly(ethylene oxide) (PEO) and poly(methyl methacrylate) (PMMA) blend (50:50 wt/wt%) with lithium triflate (LiCF 3SO 3) as a dopant ionic salt at stoichiometric ratio [EO + (CO)]:Li + = 9:1, poly(ethylene glycol) (PEG) as plasticizer (10 wt%) and montmorillonite (MMT) clay as nanofiller (3 wt%) have been prepared by solution cast followed by melt–pressing method. The X–ray diffraction study infers that the (PEO–PMMA)–LiCF 3SO 3 electrolyte is predominantly amorphous, but (PEO–PMMA)–LiCF 3SO 3–10 wt% PEG electrolyte has some PEO crystalline cluster, whereas (PEO–PMMA)–LiCF 3SO 3–10 wt% PEG–3 wt% MMT electrolyte is an amorphous with intercalated and exfoliated MMT structures. The complex dielectric function, ac electrical conductivity, electric modulus and impedance spectra of these electrolytes have been investigated over the frequency range 20 Hz to 1 MHz. These spectra have been analysed in terms of the contribution of electrode polarization phenomenon in the low frequency region and the dynamics of cations coordinated polymer chain segments in the high frequency region, and also their variation on the addition of PEG and MMT in the electrolytes. The temperature dependent dc ionic conductivity, dielectric relaxation time and dielectric strength of the plasticized nanocomposite electrolyte obey the Arrhenius behaviour. The mechanism of ions transportation and the dependence of ionic conductivity on the segmental motion of polymer chain, dielectric strength, and amorphicity of these electrolytes have been explored. The room temperature ionic conductivity values of the electrolytes are found ∼10 −5 S cm −1, confirming their use in preparation of all-solid-state ion conducting devices. 相似文献
5.
The polyethylene oxide (PEO) based lithium ion conducting polymer electrolytes complexed with lithium trifluoromethanesulfonate (LiCF 3SO 3 or LiTf) plasticized with an ionic liquid 1-ethyl 3-methyl imidazolium trifluoromethanesulfonate (EMITf) have been reported. Morphological, spectroscopic, thermal and electrochemical investigations demonstrate promising characteristics of the polymer films, suitable as electrolyte in various energy storage/conversion devices. Significant structural changes have been observed in the polymer electrolyte due to the ionic liquid addition, investigated by X-ray diffraction (XRD) and optical microscopy. The ion-polymer interaction, particularly the interaction of imidazolium cation with PEO chains, has been evidenced by IR and Raman spectroscopic studies. The optimized composition of the polymer electrolyte i.e. PEO 25.LiTf + 40 wt.% EMITf offer room temperature ionic conductivity of ~ 3 × 10 − 4 S cm − 1 with wide electrochemical stability window and excellent thermal stability. The ‘σ versus 1/T’ curves show apparent Arrhenius behavior below and above melting temperature. The ionic conductivity has been observed due to Li + ions, as confirmed from 7Li-NMR studies, though the component ions of ionic liquid and anions also contribute significantly to the overall conductivity. 相似文献
6.
A series of different composition of polymer electrolytes-based on poly(vinyl chloride) (PVC) as host polymer, lithium tetraborate
(Li 2B 4O 7) as dopant salt, and dibutyl phthalate (DBP) as plasticizer were prepared by solution casting method. The interaction between
the PVC, Li 2B 4O 7, and DBP were studied by Fourier transform infrared. The shifting, broadening, and splitting of transmission peaks were the
evidences of complexation. The highest ionic conductivity polymer electrolyte of 2.83 × 10 −6 S/cm was achieved at ambient temperature upon addition of 30 wt.% of DBP. In addition, the temperature-dependent conductivity,
frequency-dependent conductivity, dielectric permittivity, and modulus studies were performed. The temperature-dependent conductivity
of the polymer electrolytes was found to obey the Arrhenius behavior. The thermal stability of polymer electrolytes was verified
by thermogravimetric analysis. The lower in glass transition temperature was proven in differential scanning calorimetry,
whereas the higher amorphous region within the polymer matrix was demonstrated in X-ray diffraction. 相似文献
7.
Solid polymer electrolytes (SPEs) based on poly (vinyl chloride)/poly (ethyl methacrylate) [PVC/PEMA] blend complexed with zinc triflate [Zn(CF 3SO 3) 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 Zn 2+ 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 Zn 2+ 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
8.
This work examines the effect of lithium trifluoromethanesulfonate (LiCF 3SO 3) 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.% LiCF 3SO 3 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. 相似文献
9.
A solid polymer electrolyte (SPE) is synthesized by solution casting technique. The SPE uses poly(ethylene oxide) PEO as a host matrix doped with lithium triflate (LiCF 3SO 3), ethylene carbonate (EC) as plasticizer and nano alumina (Al 2O 3) as filler. The polymer electrolytes are characterized by Impedance Spectroscopy (IS) to determine the composition of the additive which gives the highest conductivity for each system. At room temperature, the highest conductivity is obtained for the composition PEO-LiCF 3SO 3-EC-15%Al 2O 3 with a value of 5.07 10 − 4 S/cm. The ionic conductivity of the polymer electrolytes increases with temperature and obeys the Arrhenius law. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) studies indicate that the conductivity increase is due to an increase in amorphous content which enhances the segmental flexibility of polymeric chains and the disordered structure of the electrolyte. Fourier transform infrared spectroscopy (FTIR) spectra show the occurrence of complexation and interaction among the components. Scanning electron microscopy (SEM) images show the changes morphology of solid polymer electrolyte. 相似文献
10.
PEO-based solid polymer electrolyte films with various concentrations of nanochitosan as filler and LiCF 3SO 3 as salt were prepared by membrane hot-press technique. Nanochitosan was prepared from chitosan by conventional chemical cure method. The prepared composite membranes were characterized by FT-IR, XRD, thermal, SEM, AFM analyses, electrochemical impedance spectroscopy, cyclic voltammetry and compatibility studies. The ionic conductivity and thermal stability of the polymer membranes were enhanced significantly by addition of nanofiller. The compatibility studies reveal that filler incorporated membrane is better compatible with lithium interface than filler free electrolyte. 相似文献
11.
Solid polymer electrolytes of high ionic conductivity are prepared using poly acrylonitrile (PAN), propylene carbonate (PC),
ethylene carbonate (EC) and LiCF 3SO 3. The polymer films are characterised by X-ray diffraction, FTIR and a.c. impedance spectroscopic techniques. The conductivity
studies of PAN-LiCF 3SO 3-PC-EC polymer electrolyte systems are carried out in the temperature range 301–373 K. The temperature dependence of the conductivity
of the polymer films obeys the VTF relation. The conductivity values are presented and the results are discussed. 相似文献
12.
Lithium salt, LiX (where X = BF 4 ? , I ?, CF 3SO 3 ? , COOCF 3 ? or ClO 4 ? ), was incorporated into epoxidized natural rubber (ENR). Thin films of LiX-ENR polymer electrolytes (PEs) were obtained via solvent casting method. These electrolytes were characterized using SEM/X-mapping, FTIR, differential scanning calorimeter, thermogravimetry analysis, and impedance spectroscopy. The trend in thermal stability and ionic conductivity of LiX-ENR PEs follow LiBF 4 > > LiCF 3SO 3 ~ LiCOOCF 3 > LiI > > LiClO 4. The LiClO 4 hardly dissociates and formed LiClO 4 aggregates within the polymer matrix that resulted in a PE with low thermal stability and low ionic conductivity. The LiCF 3SO 3, LiCOOCF 3, and LiI, however, exert moderate interactions with the ENR, and their respective PEs exhibit moderate ionic conductivity and thermal property. The occurrence of epoxide ring opening and complexation or cross-linking reactions in and between the ENR chains that involve BF 4 ? ions have produced a LiBF 4-ENR PE with superior thermal property and ionic conductivity as compared to other PEs studied in this work. 相似文献
13.
In recent years, solid polymer electrolytes have been extensively studied due to its flexibility, electrochemical stability, safety, and long life for its applications in various electrochemical devices. Interaction of LiCF3SO3 and TiO2 nanofiller in the optimized composition of PVA:PVdF (80:20—system-A possessing σ ~ 2.8 × 10−7 Scm−1 at 303 K) blend polymer electrolyte have been analyzed in the present study. LiCF3SO3 has been doped in system-A, and the optimized LiCF3SO3 doped sample (80:20:15-system-B possessing σ ~ 2.7 × 10−3 Scm−1 at 303 K) has been identified. The effect of different concentration of TiO2 in system-B has been analyzed and the optimized system is considered as system-C (σ ~ 3.7 × 10−3 Scm−1 at 303 K). The cost effective, solution casting technique has been used for the preparation of the above polymer electrolytes. Vibrational, structural, mechanical, conductivity, thermal, and electrochemical properties have been studied using FTIR, XRD, stress-strain, AC impedance spectroscopic technique, DSC and TGA, LSV, and CV respectively to find out the optimized system. System-C possessing the highest ionic conductivity, higher tensile strength, low crystallinity, high thermal stability, and high electrochemical stability (greater than 5 V vs Li/Li+) is well suitable for lithium ion battery application. 相似文献
14.
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(CF 3SO 3) 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(CF 3SO 3) 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
15.
A solid polymer electrolyte (SPE) composites consisting blend of poly(ethylene oxide) (PEO) and poly(ethylene glycol) (PEG) as the polymer host with LiCF 3SO 3 as a Li + cation salt and TiO 2 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 %), LiCF 3SO 3 (15 %), ethylene carbonate (5 %), and TiO 2 (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
16.
Nanocomposite solid polymer electrolytes (NSPEs) based on poly(vinylidene fluoride) (PVDF) were prepared by dispersing two kinds of organoclay (Cloisite ® 30B, Cloisite ® 15A) consisting of silicate layers in the polymer matrix. The effect of affinity between PVDF and organoclay as the filler on ionic conductivity was investigated in relation to its content, dispersed condition of organoclay, and structural changes of nanocomposites. The characterizations of PVDF-based nanocomposites with various organoclay contents were carried out by XRD, TEM, DSC, and DMA. In order to confirm the ion conduction properties of NSPEs with LiCF 3SO 3 at room temperature, ac impedance analyzer and FT-IR spectrometer were used. As a result, a higher ionic conductivity appeared in the case of NSPE with C15A than that with C30B and the maximum conductivity was 1.04 × 10 –3 S/cm for the NSPE containing 5 wt% of C15A and 40 wt% of LiCF 3SO 3. 相似文献
17.
Surface treatment of TiO 2 was done by immersing filler particles in 2 and 4 % sulphuric acid (H 2SO 4) aqueous solutions. Untreated, 2 and 4 % H 2SO 4-treated TiO 2 were referred as neutral, weakly acidic, and acidic TiO 2, respectively. Composite polymer electrolytes (CPEs) based on hexanoyl chitosan–polystyrene blend were prepared by using lithium trifluromethanesulfonate (LiCF 3SO 3) as the doping salt and three different types of the TiO 2 fillers. X-ray diffraction (XRD) results showed that the addition of TiO 2 reduced the crystalline fraction of the electrolytes. The conductivity performance of the CPEs varied in the order: acidic?<?weakly acidic?<?TiO 2 free?<?neutral TiO 2. A model based on the interaction between Lewis acid–base sites of TiO 2 with ionic species of LiCF 3SO 3 has been proposed to understand the conductivity mechanism brought about by the different types of fillers. The conductivity enhancement by neutral TiO 2 is attributed to the increase in the mobility of Li + cations. Acidic TiO 2 decreased the conductivity by decreasing the anionic contribution. The conductivity variation with filler content was discussed on the basis of the number of free ions. 相似文献
18.
The plasticized polymer electrolyte composed of polyvinylchloride (PVC) and polyvinylidene fluoride (PVdF) as host polymer,
the mixture of ethylene carbonate and propylene carbonate as plasticizer, and LiCF 3SO 3 as a salt was studied. The effect of the PVC-to-PVdF blend ratio with the fixed plasticizer and salt content on the ionic
conduction was investigated. The electrolyte films reveal a phase-separated morphology due to immiscibility of the PVC with
plasticizer. Among the three blend ratios studied, 3:7 PVC–PVdF blend ratio has shown enhanced ionic conductivity of 1.47 × 10 −5 S cm −1 at ambient temperature, i.e., the ionic conductivity decreased with increasing PVC-to-PVdF ratio and increased with increasing
temperature. A temperature dependency on ionic conductivity obeys the Arrhenius behavior. The melting endotherms corresponding
to vinylidene (VdF) crystalline phases are observed in thermal analysis. Thermal study reveals the different levels of uptake
of plasticizer by VdF crystallites. The decrease in amorphousity with increase in PVC in X-ray diffraction studies and larger
pore size appearance for higher content of PVC in scanning electron microscopy images support the ionic conductivity variations
with increase in blend ratios. 相似文献
19.
Thin films of poly(methyl methacrylate) (PMMA) with lithium triflate (LiCF 3SO 3) were prepared by using the solution-casting method with PMMA as the host polymer. Ionic conductivity and dielectric measurements
were carried out on these films. The highest conductivity for polymer electrolyte with a ratio of 65:35 was found to be 9.88 × 10 −5 S cm −1, which is suitable for the production of mobile phone battery. Thermal gravimetric analysis was carried out to evaluate the
thermal stability of the polymer electrolyte. The addition of salts will increase thermal stability of the polymer electrolyte. 相似文献
20.
A solid polymer electrolytes (SPE) comprising blend of poly(ethylene oxide; PEO) and epoxidized natural rubber as a polymer
host and LiCF 3SO 3 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 LiCF 3SO 3, and this composition exhibited an Arrhenius-like behavior with the activation energy of 0.42 eV and the preexponential factor
of 1.6 × 10 3 Scm −1. 相似文献
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