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1.
Plasticized polymer electrolytes composed of poly(methyl methacrylate) (PMMA) as the host polymer and lithium bis(trifluoromethanesulfonyl)imide
LiN(CF3SO2)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(CF3SO2)2. The complexation effect of salt was investigated using FTIR. It showed some simple overlapping and shift in peaks between
PMMA and LiN(CF3SO2)2 salt in the polymer electrolyte. Ethylene carbonate (EC) and propylene carbonate (PC) were added to the PMMA–LiN(CF3SO2)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(CF3SO2)2–EC–PC solid polymer electrolyte which showed a maximum value at 6.11 × 10−5 S cm−1 for 2% SiO2. 相似文献
2.
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. 相似文献
3.
Kamlesh Pandey Mrigank Mauli Dwivedi Mridula Tripathi Markandey Singh S. L. Agrawal 《Ionics》2008,14(6):515-523
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. 相似文献
4.
Conductivity studies of plasticized anhydrous PEO-KOH alkaline solid polymer electrolyte 总被引:1,自引:0,他引:1
Polyethylene oxide (PEO)–potassium hydroxide (KOH)-based alkaline solid polymer electrolyte films have been prepared by using
methanol as solvent. The highest room temperature ionic conductivity of (2.1 ± 0.5) × 10−8 S cm−1 was achieved for the composition of 70 wt% PEO:30 wt% KOH. The addition of plasticizer, ethylene carbonate, propylene carbonate,
or polyethylene glycol to the highest conductivity of PEO–KOH system helps to increase the ambient ionic conductivity to the
order of 10−6–10−4 S cm−1. The log σ vs 1/T plot of PEO–KOH showed a small conductivity decrease at 50–60 °C range. The small decrease and the hysteresis that occur
during the heating–cooling cycle was overcome by the presence of the plasticizer. X-ray diffraction observation supports the
conductivity results. 相似文献
5.
A new proton-conductive membrane (PCM) based on poly (vinyl alcohol) and ammonium sulfate (NH4)2SO4 complexed with sulfuric acid and plasticized with ethylene carbonate (EC) at different weight percent were prepared by casting
technique. The structural properties of these electrolyte films were examined by XRD studies. The XRD patterns of all the
prepared polymer electrolytes reveal the amorphous nature of the films. ac conductivity and dielectric spectra of the electrolyte
were studied with changing EC content from weight 0.00 to 0.75 g. A maximum conductivity of 7.3 × 10−5 S cm−1 has been achieved at ambient temperature for PCM containing 0.25 g of ethylene carbonate. The electrical conductivity σ, dielectric constant ε′ and dielectric loss ε″ of PCM in frequency range (100 Hz to 100 KHz), and temperature range (300–400 K) were carried out. Measurement of transference
number was carried out to investigate the nature of charge transport in these polymer electrolyte films using Wagner’s polarization
technique. Transport number data showed that the charge transport in these polymer electrolyte systems was predominantly due
to ions. The electrolyte with the highest electrical conductivity was used in the fabrication of a solid-state electrochemical
cell with the configuration (Mg/PCM/PbO2). Various cell parameters ldensity, and current density were determined. The fabricated cells gave capacity of 650 μAh and
have an internal resistance of 11.6 kΩ. 相似文献
6.
Li-ion rechargeable batteries based on polymer electrolytes are of great interest for solid state electrochemical devices
nowadays. Many studies have been carried out to improve the ionic conductivity of polymer electrolytes, which include polymer
blending, incorporating plasticizers and filler additives in the electrolyte systems. This paper describes the effects of
incorporating nano-sized MnO2 filler on the ionic conductivity enhancement of a plasticized polymer blend PMMA–PEO–LiClO4–EC electrolyte system. The maximum conductivity achieved is within the range of 10−3 S cm−1 by optimizing the composition of the polymers, salts, plasticizer, and filler. The temperature dependence of the polymer
conductivity obeys the VTF relationship. DSC and XRD studies are carried out to clarify the complex formation between the
polymers, salts, and plasticizer. 相似文献
7.
A sodium ion conducting composite polymer electrolyte (CPE) prepared by solution-caste technique by dispersion of an electrochemically
inert ceramic filler (SnO2) in the PEO–salt complex matrix is reported. The effect of filler concentration on morphological, electrical, electrochemical,
and mechanical stability of the CPE films has been investigated and analyzed. Composite nature of the films has been confirmed
from X-ray diffraction and scanning electron microscopy patterns. Room temperature d.c. conductivity observed as a function
of filler concentration indicates an enhancement (maximum) at 1–2 wt% filler concentration followed by another maximum at
∼10 wt% SnO2. This two-maxima feature of electrical conductivity as a function of filler concentration remains unaltered in the CPE films
even at 100 °C (i.e., after crystalline melting), suggesting an active role of the filler particles in governing electrical
transport. Substantial enhancement in the voltage stability and mechanical properties of the CPE films has been noticed on
filler dispersion. The composite polymer films have been observed to be predominantly ionic in nature with t
ion ∼ 0.99 for 1–2 wt% SnO2. However, this value gets lowered on increasing addition of SnO2 with t
ion ∼ 0.90 for 25 wt% SnO2. A calculation of ionic and electronic conductivity for 25 wt% of SnO2 film works out to be ∼2.34 × 10−6 and 2.6 × 10−7 S/cm, respectively. 相似文献
8.
Arun Kumar Dorai S. Selvasekarapandian Nithya Hellar Sakunthala Ayyasamy Hema Muthusamy 《Ionics》2010,16(6):481-486
Thin films of ionic conductors have low internal resistance. Hence, it could be used as an electrolyte material in sensors
to operate at ambient temperatures. Cerium fluoride, a unipolar fluoride ion conductor, has got a different application in
electrochemical sensor. In the present work, cerium fluoride thin films have been prepared by physical vapor deposition method
and their electrical properties are studied. X-ray diffraction studies reveal the polycrystalline nature of the prepared thin
films and the structure of the material. Scanning electron microscopy (SEM) images show grain-like structures. Conductivity
analysis of the thin films has been studied by ac impedance analysis and the maximum conductivity value is found to be 1.04 × 10−6 S cm−1. The impedance spectra emphasize intergranular conduction in the prepared thin films. 相似文献
9.
This paper describes the preparation and conductivity studies of polyindole–ZnO composite polymer electrolyte (CPE) with LiClO4. Polyindole–ZnO-based polymer nanocomposites were prepared by chemical method and characterized by XRD, infrared (IR), scanning
electron microscope (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The IR spectrum confirms
the intermolecular interaction between polyindole and ZnO. The significant spectral changes of polyindole and ZnO nancomposites
reveal the strong interaction between polyindole and ZnO nanoparticles. The structural morphologies of the ZnO, polyindole,
and polyindole–ZnO are obtained from SEM. The TEM image of polyindole nanocomposite shows that ZnO is embedded in polyindole
matrix. An enhanced conductivity of 4.405 × 10−7 S cm−1 at 50 °C for the CPE was determined from impedance studies. 相似文献
10.
Thin films of poly(methyl methacrylate) (PMMA) with lithium triflate (LiCF3SO3) 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
11.
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 LiCF3SO3 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
12.
A biopolymer electrolyte system having conductivity ∼1.3 × 10−4 S cm−1 has been prepared using potato starch, NaI, glutaraldehyde and poly(ethylene glycol) (PEG; molecular weight = 300). High
ionic transference numbers (∼0.99) of the material confirmed its electrolytic behaviour. Conductivity and dielectric behaviour
as a function of frequency has been studied. Conductivity follows ‘universal power law’ (σ = σ
0 + Aω
n
) with exponent ‘n’ varying from 0.94 to 1.18. Cross-linking and plasticization increases long pathways motion of charge carriers, comparable
to sample dimension. Humidity-independent behaviour (up to 80% relative humidity), of impedance and water intake by the system,
indicates the system’s potentiality as a promising candidate for humidity immune device fabrication. The addition of PEG has
a twofold effect on the material’s conductivity. It not only increases conductivity but also improves the material’s immunity
towards humid atmosphere. 相似文献
13.
Solvent-free films of poly (ethylene oxide)–silver triflate (PEO–AgCF3SO3)/MgO-based nanocomposite polymer electrolytes (PEO)50AgCF3SO3–x wt.% MgO (x = 1, 3, 5, 7, and 10) obtained using solution casting technique were found to exhibit an appreciably good complexation of
MgO nanofiller within the polymer electrolyte system and non-Debye type of relaxation as revealed by Fourier transform infrared
and complex impedance analyses. Optimized filler (5 wt.% MgO) when incorporated into the polymer electrolyte resulted in a
maximum electrical conductivity of 2 × 10−6 S cm−1 in conjunction with a silver ionic transference number (t
Ag+) of 0.23 at room temperature (298 K). Detailed structural, thermal, and surface morphological investigation indicated a slight
reduction in the degree of crystallinity owing to the addition of MgO nanofiller. 相似文献
14.
The conducting polymer electrolyte films consisting of polyacrylonitrile (PAN) as the host polymer, lithium triflate (LiCF3SO3) and sodium triflate (NaCF3SO3) 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.%
LiCF3SO3 film and the PAN + 24 wt.% NaCF3SO3 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 + LiCF3SO3 and PAN + NaCF3SO3 systems follows Arrhenius equation in the temperature range of 303 to 353 K. The PAN containing 24 wt.% LiCF3SO3 film has a higher ionic conductivity and lower activation energy compared to the PAN containing 26 wt.%LiCF3SO3 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
15.
The effect of plasticizer and TiO2 nanoparticles on the conductivity, chemical interaction and surface morphology of polymer electrolyte of MG49–EC–LiClO4–TiO2 has been investigated. The electrolyte films were successfully prepared by solution casting technique. The ceramic filler,
TiO2, was synthesized in situ by sol-gel process and was added into the MG49–EC–LiClO4 electrolyte system. Alternating current electrochemical impedance spectroscopy was employed to investigate the ionic conductivity
of the electrolyte films at 25 °C, and the analysis showed that the addition of TiO2 filler and ethylene carbonate (EC) plasticizer has increased the ionic conductivity of the electrolyte up to its optimum
level. The highest conductivity of 1.1 × 10−3 Scm−1 was obtained at 30 wt.% of EC. Fourier transform infrared spectroscopy measurement was employed to study the interactions
between lithium ions and oxygen atoms that occurred at carbonyl (C=O) and ether (C-O-C) groups. The scanning electron microscopy
micrograph shows that the electrolyte with 30 wt.% EC posses the smoothest surface for which the highest conductivity was
obtained. 相似文献
16.
Hybrid solid polymer electrolyte films comprising of poly(vinyl acetate) (PVAc), poly(methyl methacrylate) (PMMA), LiClO4, and propylene carbonate are prepared by solution casting technique by varying the salt concentration. In this study, PVAc/PMMA
polymer blend ratio is fixed as 25:75 on the basis of conductivity and mechanical stability of the film. X-ray diffraction,
Fourier transform infrared impedance, thermogravimetry/differential thermal analysis and scanning electron microscopy studies
are carried out for the polymer electrolytes. The maximum ionic conductivity is found to be 4.511 × 10−4 S cm−1 at 303 K for the plasticized polymer electrolyte with 8 wt.% of LiClO4. The ionic conductivity is found to decrease with an increase of LiClO4 concentration. 相似文献
17.
In order to enhance the ionic conductivity of polyethylene oxide (PEO)–KI(80:20) based alkaline polymer electrolytes, nanosized inorganic filler ZnS has been incorporated into PEO–KI matrix and the corresponding nanocomposite polymer electrolytes are synthesized by the usual solution casting procedure. Atomic force microscope image of composite polymer electrolyte exhibits that the introduction of ZnS nanoparticles changes the surface morphology and aggregates them to form an arborization pattern. The prepared nanocomposite polymer electrolyte reveals an ionic conductivity of about 10?4 S cm?1 for 5 wt% ZnS at room temperature. 相似文献
18.
Atmospheric plasma spray is a fast and economical process for deposition of yttria-stabilized zirconia (YSZ) electrolyte for
solid oxide fuel cells. YSZ powders have been used to prepare plasma-sprayed thin ceramic films on the metallic substrate
employing plasma spray technology at atmospheric pressure. Alumina doping was employed to improve the structural characteristics
and electrical properties of YSZ. The effect of alumina addition from 1 to 5 wt.% on the properties of plasma-sprayed YSZ
films was investigated. It was found that the gas permeability of the Al-doped YSZ electrolyte layer reached a level of 8.6 × 10−7 cm4 gf−1 s−1, which is a necessary value for the practical operation of solid oxide fuel cells. Alumina doping considerably increased
the ionic conductivity of plasma-sprayed YSZ. The open circuit voltage of the alumina-doped YSZ coating was approximately
equal to the theoretical value for dense YSZ material. 相似文献
19.
Hellar Nithya S. Selvasekarapandian P. Christopher Selvin Dorai Arun Kumar Muthusamy Hema 《Ionics》2011,17(7):587-593
The plasticized polymer electrolyte consisting of poly(epichlorohydrin-ethyleneoxide) [P(ECH-EO)], lithium perchlorate (LiClO4) and γ-butyrolactone (γ-BL) have been prepared by simple solution casting technique. The polymer–salt–plasticizer complex
has been confirmed by XRD analysis. The ionic conductivity studies have been carried out using AC impedance technique. The
effect of plasticizer (γ-BL) on ionic conductivity has been discussed with respect to different temperatures. The maximum
value of ionic conductivity is found to be 1.3 × 10−4 Scm−1 for 70P(ECH-EO):15γ-BL:15LiClO4 at 303 K. The temperature dependence of the plasticized polymer electrolyte follows the Vogel–Tamman–Fulcher formalism. The
activation energy is found to decrease with the increase in plasticizer. 相似文献
20.
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 (LiCF3SO3) has been incorporated into the polymer electrolyte systems. Two types of ceramic fillers, i.e., SiO2 and Al2O3, 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–LiCF3SO3) system is 1.36 × 10−5 S cm−1. On addition of the SiO2 filler and Al2O3 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–CH3 band.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7-9, 2006. 相似文献