共查询到20条相似文献,搜索用时 78 毫秒
1.
An attempt has been made in the present work to combine gel and composite polymer electrolyte routes together to form a composite
polymeric gel electrolyte that is expected to possess high ionic conductivity with good mechanical integrity. Polyethylene
glycol (PEG) based composite gel electrolytes using polyvinyl alcohol (PVA) as guest polymer have been synthesized with 1
molar solution of ammonium thiocyanate (NH4SCN) in dimethyl sulphoxide (DMSO) and electrically characterized. The ionic conductivity measurements indicate that PEG:PVA:NH4SCN-based composite gel electrolytes are superior (σ
max = 5.7 × 10−2 S cm−1) to pristine electrolytes (PEG:NH4SCN system) and conductivity variation with filler concentration remains within an order of magnitude. The observed conductivity
maxima have been correlated to PEG:PVA:NH4SCN-and PVA:NH4SCN-type complexes. Temperature dependence of conductivity profiles exhibits Arrhenius behaviour in low temperature regime
followed by VTF character at higher temperature.
相似文献
2.
F. F. Hatta M. Z. A. Yahya A. M. M. Ali R. H. Y. Subban M. K. Harun A. A. Mohamad 《Ionics》2005,11(5-6):418-422
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
3.
Blend based polymer electrolytes composed of poly (methyl methacrylate) (PMMA), poly(vinylalcohol) (PVA) and LiClO4 are prepared using solvent casting technique. The polymer films are characterized by XRD and FTIR studies to determine the
molecular environment for the conducting ions. These polymer films have been investigated in terms of ionic conductivity using
the results of impedance studies. The influence of the blend composition on the electrochemical behaviour is also discussed.
The highest room temperature conductivity obtained for the film consisting of PMMA, PVA, LiClO4 and DMP is 0.06×10−3 S/cm at 303 K. The PMMA-PVA blend based polymer electrolytes look very desirable and promising for lithium battery applications. 相似文献
4.
An attempt has been made to prepare a new proton conducting polymer electrolyte based on polyvinyl alcohol (PVA) doped with
NH4NO3 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% NH4NO3-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
5.
Solid polymer electrolytes based on poly(vinyl alcohol) (PVA) doped with NH4Br have been prepared by the solution-casting method. The complex formation between the polymer and the salt has been confirmed
by Fourier transform infrared spectroscopy. The highest conductivity at 303 K has been found to be of the order of 10−4 Scm−1 for 25 mol% NH4Br-doped PVA system. The ionic transference number of polymer electrolyte has been estimated by Wagner’s polarization method,
and the results reveal that the conducting species are predominantly ions.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006. 相似文献
6.
Polyvinyl alcohol (PVA) and potassium hydroxide (KOH) have been used to prepare alkaline solid polymer electrolytes (ASPE) films. The films were stored in a dry environment for 30 and 100 days. The highest room temperature conductivity for the PVA:KOH film with weight percentage ratio of 1:0.67 during storage for 30 and 100 days were (8.5±0.2)×10−4 and (1.3±0.1)×10−7 S cm−1, respectively. The conductivity–temperature behaviour after 30 and 100 days of storage of the alkaline polymer electrolytes is Arrhenian and liquid-like. The structural, morphological and thermal studies of the ASPE films are also presented in this paper. 相似文献
7.
Gel polymer electrolytes consisting of 49% PMMA grafted polyisoprene-LiCF3SO3, were plasticized with propylene carbonate (PC) are reported. The effect of PC on the electrochemical properties of the polymer
electrolyte has been investigated. Analysis of FTIR spectra shows the interaction of salt and plasticizers with the polymer
chain. The ionic conductivity was measured and exhibited a maximum value of 10−4 S/cm. The temperature dependence of the electrical conductivity follows the Arrhenius law.
Paper presented at the International Conference on Functional Materials and Devices 2005, Kuala Lumpur, Malaysia, June 6 –
8, 2005. 相似文献
8.
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
9.
A polymer blend electrolyte based on polyvinyl alcohol (PVA) and polyacrylonitrile (PAN) was prepared by a simple solvent casting technique in different compositions. The ionic conductivity of polymer blend electrolytes was investigated by varying the PAN content in the PVA matrix. The ionic conductivity of polymer blend electrolyte increased with the increase of PAN content. The effect of lithium salt concentrations was also studied for the polymer blend electrolyte of high ionic conductivity system. A maximum ionic conductivity of 3.76×10−3 S/cm was obtained in 3 M LiClO4 electrolyte solution. The effect of ionic conductivity of polymer blend electrolyte was measured by varying the temperature ranging from 298 to 353 K. Linear sweep voltammetry and DC polarization studies were carried out to find out the stability and lithium transference number of the polymer blend electrolyte. Finally, a prototype cell was assembled with graphite as anode, LiMn2O4 as cathode, and polymer blend electrolyte as the electrolyte as well as separator, which showed good compatibility and electrochemical stability up to 4.7 V. 相似文献
10.
M. Hema S. Selvasekerapandian A. Sakunthala H. Nithya 《Physica B: Condensed Matter》2008,403(17):2740-2747
Polymer electrolyte based on PVA doped with different concentrations of NH4Br has been prepared by solution casting technique. The complexation of the prepared polymer electrolytes has been studied using X-ray diffraction (XRD) and Fourier transform infra red (FTIR) spectroscopy. The maximum ionic conductivity (5.7×10−4 S cm−1) has been obtained for 25 mol% NH4Br-doped PVA polymer electrolyte. The temperature dependence of ionic conductivity of the prepared polymer electrolytes obeys Arrhenius law. The ionic transference number of mobile ions has been estimated by dc polarization method and the results reveal that the conducting species are predominantly ions. The dielectric behavior of the polymer electrolytes has been analyzed using dielectric permittivity and electric modulus spectra. 相似文献
11.
Poly(vinyl acetate), poly(vinylidene fluoride–hexafluoropropylene), lithium perchlorate salt, and the different plasticizer-based
gel polymer electrolytes were prepared by solvent-casting technique. The structural and the complex formation have been confirmed
by X-ray diffraction spectroscopic analysis. Thermal stability of the different plasticizer-added electrolyte films has been
analyzed by means of thermogravimetric analysis. Ionic conductivity of the electrolyte samples has been found as a function
of temperature and the plasticizers. Among the various plasticizers, ethylene carbonate-based complexes exhibit maximum ionic
conductivity value of the order of 10−4 Scm−1. Finally, the microstructure of the maximum ionic conductivity sample has been depicted with the help of scanning electron
microscope analysis. 相似文献
12.
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
13.
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
14.
G. Hirankumar S. Selvasekarapandian M. S. Bhuvaneswari R. Baskaran M. Vijayakumar 《Ionics》2004,10(1-2):135-138
A proton conducting polymer electrolytes of pure polyvinyl alcohol and polyvinyl alcohol complexed with ammonium acetate having
different compositions have been prepared by solution cast technique. FTIR spectrum confirms the complexation process. The
conductivity of the pure polyvinyl alcohol is in the order 10−10 S/cm at ambient temperature and its value increases 104 times when complexed with 20% ammonium acetate. The Arrhenius plot for all electrolyte shows two different regions above
and below the glass transition temperature. A high dielectric loss value is observed for the case of complexed PVA in comparison
to pure PVA. Based on the study of relaxation spectra, it is found that the relaxation time decreases with increase in temperature
and dopant concentration.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
15.
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 (LiClO4) 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.%)/LiClO4 (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
16.
Copper-ion conducting solid-polymer electrolyte systems based on Polyvinyl alcohol (PVA) has been prepared by solution cast
technique. UV-VIS data show a broad peak in the wavelength region 600–800 nm due to complex formation. The 30 wt.% Cu(NO3)2 doped system has a maximum conductivity of 1.6×10−5 Scm−1 at room temperature. The conductance spectrum shows two distinct regions: a dc plateau and a dispersive region. The dielectric
spectra show an increase in the dielectric constant with decreasing frequency. The transference number measurements reveal
that the transport in these electrolytes is mainly due to ions.
Paper presented at the International Conference on Functional Materials and Devices 2005, Kuala Lumpur, Malaysia, June 6 –
8, 2005. 相似文献
17.
Non-aqueous polymer gel electrolytes containing trifluoromethanesulfonic acid (HCF3SO3) and polyethylene oxide (PEO) as the gelling polymer has been studied. The increase in conductivity observed with the addition
of PEO to liquid electrolytes has been explained to be due to the breaking of ion aggregates present in electrolytes at higher
acid concentrations. The increase in free H+ ion concentration upon breaking of ion aggregates has also been observed in pH measurements and viscosity of gel electrolytes
has been found to increase with PEO addition. Polymer gel electrolytes containing dimethylacetamide (DMA) have σ ∼ 10−2 S/cm at room temperature and are stable over −50 to 125 °C range of temperature. Gels based on propylene carbonate (PC) and
ethylene carbonate (EC) are stable in the −50 to 40 °C temperature range and loose their gelling nature above 40 °C. 相似文献
18.
Non-aqueous polymer gel electrolytes containing trifluoromethanesulfonic acid (HCF3SO3) and polyethylene oxide (PEO) as the gelling polymer has been studied. The increase in conductivity observed with the addition
of PEO to liquid electrolytes has been explained to be due to the breaking of ion aggregates present in electrolytes at higher
acid concentrations. The increase in free H+ ion concentration upon breaking of ion aggregates has also been observed in pH measurements and viscosity of gel electrolytes
has been found to increase with PEO addition. Polymer gel electrolytes containing dimethylacetamide (DMA) have σ ∼ 10−2 S/cm at room temperature and are stable over −50 to 125 °C range of temperature. Gels based on propylene carbonate (PC) and
ethylene carbonate (EC) are stable in the −50 to 40 °C temperature range and loose their gelling nature above 40 °C. 相似文献
19.
Poly (vinylchloride) (PVC)-LiBF4 polymer electrolytes plasticized with DBP in different mole ratios have been studied by FTIR and Impedance Spectroscopic
techniques. The complexation has been confirmed from FTIR studies. The maximum room temperature conductivity (2.1·.10−7 S·.cm−1) has been observed for PVC-LiBF4-DBP (10-5-85 mole%) complex. The temperature dependence of the conductivity of the polymer films seems to obey the VTF relation.
The conductivity values are presented and the results are discussed. 相似文献
20.
Polymer electrolyte membranes, comprising of poly(methyl methacrylate) (PMMA), lithium tetraborate (Li2B4O7) as salt and dibutyl phthalate (DBP) as plasticizer were prepared using a solution casting method. The incorporation of DBP
enhanced the ionic conductivity of the polymer electrolyte. The polymer electrolyte containing 70 wt.% of poly(methyl methacrylate)–lithium
tetraborate and 30 wt.% of DBP presents the highest ionic conductivity of 1.58 × 10−7 S/cm. The temperature dependence of ionic conductivity study showed that these polymer electrolytes obey Vogel–Tamman–Fulcher
(VTF) type behaviour. Thermogravimetric analysis (TGA) was employed to analyse the thermal stability of the polymer electrolytes.
Fourier transform infrared (FTIR) studies confirmed the complexation between poly(methyl methacrylate), lithium tetraborate
and DBP. 相似文献