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1.
A solid polymer electrolyte comprising blend of poly(ethylene oxide) and 50% epoxidized natural rubber (ENR50) as a polymer
host, LiCF 3SO 3 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. 相似文献
2.
The conducting polymer electrolyte films consisting of polyacrylonitrile (PAN) as the host polymer, lithium triflate (LiCF 3SO 3) and sodium triflate (NaCF 3SO 3) as inorganic salts were prepared by the solution-cast technique. The pure PAN film was prepared as a reference. The ionic
conductivity for the films is characterized using impedance spectroscopy. The room temperature conductivity for the PAN + 26 wt.%
LiCF 3SO 3 film and the PAN + 24 wt.% NaCF 3SO 3 film is 3.04 × 10 −4 S cm −1 and 7.13 × 10 −4 S cm −1, respectively. XRD studies show that the complexation that has occurred in the PAN containing salt films and complexes formed
are amorphous. The FTIR spectra results confirmed the complexation has taken place between the salt and the polymer. These
results correspond with surface morphology images obtained from SEM analysis. The conductivity–temperature dependence of the
highest conducting film from PAN + LiCF 3SO 3 and PAN + NaCF 3SO 3 systems follows Arrhenius equation in the temperature range of 303 to 353 K. The PAN containing 24 wt.% LiCF 3SO 3 film has a higher ionic conductivity and lower activation energy compared to the PAN containing 26 wt.%LiCF 3SO 3 film. These results can be explained based on the Lewis acidity of the alkali ions, i.e., the interaction between Li + ion and the nitrogen atom of PAN is stronger than that of Na + ion. 相似文献
3.
We report a new kind of polyethylene oxide, PEO–LiCF 3SO 3-based composite polymer electrolyte, containing active copper oxide (CuO) nanoparticles with dibutyl phthalate (DBP) prepared
by solution-cast technique. The incorporation of 10 wt.% DBP and 5 wt.% CuO to the salted polymer showed a significant conductivity
enhancement with maximum conductivity 2.62 × 10 −4 Scm −1 at room temperature. This could be attributed to the increasing of amorphous phase content and structural changes in the
polymer electrolyte. Arrhenius plot suggest that temperature-dependent conductivity is a thermally activated process. 相似文献
4.
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
5.
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
6.
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
7.
Variable chain length di-urethane cross-linked poly(oxyethylene) (POE)/siloxane hybrid networks were prepared by application
of a sol-gel strategy. These materials, designated as di-urethanesils (represented as d-Ut(Y′), where Y′ indicates the average
molecular weight of the polymer segment), were doped with lithium triflate (LiCF 3SO 3). The two host hybrid matrices used, d-Ut(300) and d-Ut(600), incorporate POE chains with approximately 6 and 13 (OCH 2CH 2) repeat units, respectively. All the samples studied, with compositions ∞ > n ≥ 1 (where n is the molar ratio of (OCH 2CH 2) repeat units per Li +), are entirely amorphous. The di-urethanesils are thermally stable up to at least 200 °C. At room temperature the conductivity
maxima of the d-Ut(300)- and d-Ut(600)-based di-urethanesil families are located at n = 1 (approximately 2.0 × 10 −6 and 7.4 × 10 −5 Scm −1, respectively). At about 100 °C, both these samples also exhibit the highest conductivity of the two electrolyte systems
(approximately 1.6 × 10 −4 and 1.0 × 10 −3 Scm −1, respectively). The d-Ut(600)-based xerogel with n = 1 displays excellent redox stability. 相似文献
8.
A novel group of polymer blend electrolytes based on the mixture of poly(vinyl acetate) (PVAc), poly(vinylidene fluoride-hexafluoropropylene)
(PVdF-HFP), and the lithium salt (LiClO 4) are prepared by solvent casting technique. Ionic conductivity of the polymer blend electrolytes has been investigated by
varying the PVAc and PVdF-HFP content in the polymer matrix. The maximum ionic conductivity has been obtained as 0.527 × 10 −4 Scm −1 at 303 K for PVAc/PVdF-HFP ((25/75) wt.%)/LiClO 4 (8 wt.%). The complex formations ascertained from XRD and FTIR spectroscopic techniques and the thermal behavior of the prepared
samples has been performed by DSC analysis. The surface morphology and the surface roughness are studied using SEM and AFM
scanning techniques respectively. 相似文献
9.
Fourier transform infrared spectroscopic and electrochemical complex impedance studies have been carried out on a series of
complexes containing poly(propylene glycol) of molecular weight 4,000 and silver triflate (AgCF 3SO 3) salt corresponding to the ether oxygen to metal cation ratios (O : M) in the range 16:1 to 12:1. The formation of ion pairs
and aggregates noticed in the case of specimens having high salt concentrations as well as the complete coordination of the
cation with the ether oxygen at low salt concentrations within the PPG4000-AgCF 3SO 3 polymer electrolyte system have been confirmed. The appearance of two weak triflate bands at 1,032 and 1,272 cm −1 in the absorption spectra in respect of low salt concentrations is indicative of the fact that triflate ions are free within
the polymer matrix. The room temperature (298 K) electrical conductivity is found to increase with increasing ether oxygen
content while exhibiting the maximum value of 7.1 × 10 −5 Scm −1 possibly due to silver ionic transport in the case of the typical composition having an O : M ratio of 16:1. 相似文献
10.
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
11.
Attenuated total reflectance–Fourier transformed infrared spectroscopy measurement is employed to study the interactions between
the components of 30% methyl-grafted natural rubber (MG30), lithium trifluromethanesulfonate (LiCF 3SO 3 or LiTF), and propylene carbonate (PC). Vibrational spectra data of LiTF reveals that the ν s(SO 3) at 1,045 cm −1, δ s(CF 3) at 777 cm −1, and C=O stretching mode at 1,728 cm −1 for MG30 have shifted to lower wave numbers in MG30–LiTF complexes indicating that complexation has occurred between MG30
and LiTF. The solvation of lithium ion is manifested in Li + ← O=C interaction as shown by the downshifting and upshifting of C=O mode at 1,788 to 1,775 cm −1 and ν as(SO 3) at 1,250 to 1258 cm −1, respectively, in LiTF–PC electrolytes. There is no experimental evidence of the interaction between MG30 and PC. Competition
between MG30 and PC on associating with lithium ion is studied, and the studies show that the interaction between MG30–LiTF
is stronger than that of the PC–LiTF in plasticized polymer–salt complexes. The effect of PC on the ionic conductivity of
the MG30–LiTF system is explained in terms of the polymer, plasticizer, and salt interactions. The temperature dependence
of conductivity of the polymer films obeys the Vogel–Tamman–Fulcher relation. Values of conductivity and activation energy
of the MG30-based polymer electrolyte systems are presented and discussed. 相似文献
12.
The effects of ceramics fillers on the polymethylmethacrylate (PMMA)-based solid polymer electrolytes have been studied using
ac impedance spectroscopy and infrared spectroscopy. The polymer film samples were prepared using solution cast technique,
tetrahydrofuran (THF) used as a solvent, and ethylene carbonate (EC) has been used as plasticizer. Lithium triflate salt (LiCF 3SO 3) has been incorporated into the polymer electrolyte systems. Two types of ceramic fillers, i.e., SiO 2 and Al 2O 3, were then implemented into the polymer electrolyte systems. The solutions were stirred for several hours before it is poured
into petri dishes for drying under ambient air. After the film has formed, it was transferred into desiccator for further
drying before the test. From the observation done by impedance spectroscopy, the room temperature conductivity for the highest
conducting film from the (PMMA–EC–LiCF 3SO 3) system is 1.36 × 10 −5 S cm −1. On addition of the SiO 2 filler and Al 2O 3 filler, the conductivity are expected to increase in the order of ∼10 −4 S cm −1. Infrared spectroscopy indicates complexation between the polymer and the plasticizer, the polymer and the salts, the plasticizer
and the salts, and the polymer and the fillers. The interactions have been observed in the C=O band, C–O–C band, and the O–CH 3 band.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7-9, 2006. 相似文献
13.
An attempt has been made to prepare a new proton conducting polymer electrolyte based on polyvinyl alcohol (PVA) doped with
NH 4NO 3 by solution casting technique. The complex formation between polymer and dissociated salt has been confirmed by X-ray diffraction
analysis. The ionic conductivity of the prepared polymer electrolyte has been found by ac impedance spectroscopic analysis.
The highest ionic conductivity has been found to be 7.5 × 10 −3 Scm −1 at ambient temperature for 20 mol% NH 4NO 3-doped PVA with low activation energy (~0.19 eV). The temperature-dependent conductivity of the polymer electrolyte follows
an Arrhenius relationship, which shows hopping of ions in the polymer matrix. 相似文献
14.
The systems poly(butadiene-co-acrylonitrile) (PBAN) - lithium salts have been studied by means of X-ray and IR spectroscopy,
optical microscopy and ac- and dc-conductivity measurements. X-ray and microscopy studies have confirmed that PBAN dissolves
LiClO 4 up to [CN]/[Li] ≈ 2: 1. IR spectra of the samples with LiAsF 6, LiCF 3SO 3 and LiClO 4 have indicated the coordination between Li + and the polar CN groups of PBAN. So, PBAN was found to be a suitable polymer matrix for SPE. The polymer films exhibited
predominant ionic conductivity. Measurements of conductivity and Li transport numbers versus temperature over a wide range
of salt concentrations revealed the existence of two concentration regions (within the limits of salt solubility) corresponding
to liquid-like and glass-like ion transport mechanisms. New solid polymer electrolyte with lithium single-ion conductivity
of 10 −3 S cm −1 at 25 – 95 °C was obtained.
Paper presented at the 4th Euroconference on Solid State Ionics, Renvyle, Galway, Ireland, Sept. 13–19, 1997 相似文献
15.
Plasticized polymer electrolytes composed of poly(methyl methacrylate) (PMMA) as the host polymer and lithium bis(trifluoromethanesulfonyl)imide
LiN(CF 3SO 2) 2 as a salt were prepared by solution casting technique at different ratios. The ionic conductivity varied slightly and exhibited
a maximum value of 3.65 × 10 −5 S cm −1 at 85% PMMA and 15% LiN(CF 3SO 2) 2. The complexation effect of salt was investigated using FTIR. It showed some simple overlapping and shift in peaks between
PMMA and LiN(CF 3SO 2) 2 salt in the polymer electrolyte. Ethylene carbonate (EC) and propylene carbonate (PC) were added to the PMMA–LiN(CF 3SO 2) 2 polymer electrolyte as plasticizer to enhance the conductivity. The highest conductivities obtained were 1.28 × 10 −4 S cm −1 and 2.00 × 10 −4 S cm −1 for EC and PC mixture system, respectively. In addition, to improve the handling of films, 1% to 5% fumed silica was added
to the PMMA–LiN(CF 3SO 2) 2–EC–PC solid polymer electrolyte which showed a maximum value at 6.11 × 10 −5 S cm −1 for 2% SiO 2. 相似文献
16.
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
17.
A novel molten salt electrolyte composed of lithium triflate (CF 3SO 3Li, LiTf), sodium triflate (CF 3SO 3Na, NaTf), and potassium triflate (CF 3SO 3K, KTf) has been prepared and characterized by thermogravimetry/differential thermal analysis (TG/DTA), electrochemical impedance
spectroscopy (EIS), and cyclic voltammetry. TG/DTA shows that the electrolyte was thermally stable when the temperature was
under 400 °C. Its thermal stability gradually decreased with increase of LiTf concentration. The ionic conductivity of molten
salt electrolyte has been evaluated by EIS and its value exceeds 10 −2 Scm −1 in the temperature range from 230 to 270 °C. The electrochemical window of the electrolyte at the molar ratio of 0.5/1/1
is about 4.7 V at 250 °C. This electrolyte with low melting point exhibits promising characteristics for high-temperature
lithium batteries. 相似文献
18.
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
19.
Ion-conducting thin film polymer electrolytes based on poly(ethylene oxide) (PEO) complexes with NaAlOSiO molecular sieves
powders has been prepared by solution casting technique. X-ray diffraction, scanning electron microscopy, differential scanning
calorimeter, and alternating current impedance techniques are employed to investigate the effect of NaAlOSiO molecular sieves
on the crystallization mechanism of PEO in composite polymer electrolyte. The experimental results show that NaAlOSiO powders
have great influence on the growth stage of PEO spherulites. PEO crystallization decrease and the amorphous region that the
lithium-ion transport is expanded by adding appropriate NaAlOSiO, which leads to drastic enhancement in the ionic conductivity
of the (PEO) 16LiClO 4 electrolyte. The ionic conductivity of (PEO) 16LiClO 4-12 wt.% NaAlOSiO achieves (2.370 ± 0.082) × 10 −4 S · cm −1 at room temperature (18 °C). Without NaAlOSiO, the ionic conductivity has only (8.382 ± 0.927) × 10 −6 S · cm −1, enhancing 2 orders of magnitude. Compared with inorganic oxide as filler, the addition of NaAlOSiO molecular sieves powders
can disperse homogeneously in the electrolyte matrix without forming any crystal phase and the growth stage of PEO spherulites
can be hindered more effectively. 相似文献
20.
In the present work, five systems of samples have been prepared by the solution casting technique. These are the plasticized
poly(methyl methacrylate) (PMMA-EC) system, the LiCF 3SO 3 salted-poly(methyl methacrylate) (PMMA-LiCF 3SO 3) system, the LiBF 4 salted-poly(methyl methacrylate) (PMMA-LiBF 4) system, the LiCF 3SO 3 salted-poly(methyl methacrylate) containing a fixed amount of plasticizer ([PMMA-EC]-LiCF 3SO 3) system, and the LiBF 4 salted-poly(methyl methacrylate) containing a fixed amount of plasticizer ([PMMA-EC]-LiBF 4) system. The conductivities of the films from each system are characterized by impedance spectroscopy. The room temperature
conductivity in the pure PMMA sample and (PMMA-EC) system is 8.57 × 10 −13 and 2.71 × 10 −11 S cm −1, respectively. The room conductivity for the highest conducting sample in the (PMMA-LiCF 3SO 3), (PMMA-LiBF 4), ([PMMA-EC]-LiCF 3SO 3), and ([PMMA-EC]-LiBF 4) systems is 3.97 × 10 −6, 3.66 × 10 −7, 3.40 × 10 −5, and 4.07 × 10 −7 S cm −1, respectively. The increase in conductivity is due to the increase in number of mobile ions, and decrease in conductivity
is attributed to ion association. The increase and decrease in the number of ions can be implied from the dielectric constant,
ɛ r-frequency plots. The conductivity–temperature studies are carried out in the temperature range between 303 and 373 K. The
results show that the conductivity is increased when the temperature is increased and obeys Arrhenius rule. The plots of loss
tangent against temperature at a fixed frequency have showed a peak at 333 K for the ([PMMA-EC]-LiBF 4) system and a peak at 363 K for the ([PMM-EC]-LiCF 3SO 3) system. This peak could be attributed to β-relaxation, as the measurements were not carried out up to glass transition temperature,
T
g. It may be inferred that the plasticizer EC has dissociated more LiCF 3SO 3 than LiBF 4 and shifted the loss tangent peak to a higher temperature.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006 相似文献
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