US EPA

4583160 

Journal Article 

Temperature dependent dielectric behaviour and structural dynamics of PEO-PMMA blend based plasticized nanocomposite solid polymer electrolyte 

Choudhary, S; Dhatarwal, P; Sengwa, RJ 

2017 

Yes 

Indian Journal of Engineering and Materials Sciences
ISSN: 0971-4588 

24 

2 

123-132 

WOS:000416613700004 

Plasticized nanocomposite solid polymer electrolyte (PNSPE) films comprising polymer blend of poly(ethylene oxide) (PEO) and poly(methyl methacrylate) (PMMA) with lithium triflate (LiCF3SO3) as a dopant ionic salt, propylene carbonate (PC) as plasticizer and montmorillonite (MMT) clay as inorganic nanofiller have been prepared by classical solution-cast and ultrasonic-microwave irradiated solution-cast methods. The X-ray diffraction study confirms predominantly amorphous phase of these PNSPE films having both the intercalated and exfoliated MMT structures. The dielectric and electrical spectra in the frequency range 20 Hz to 1 MHz of the PNSPE films exhibits the relaxation processes corresponding to charging and discharging of electric double layers in the low frequency region and the cations coordinated polymers chain segmental motion in the high frequency region. The complex dielectric permittivity and ac electrical conductivity increase, whereas the impedance values decrease with the increase of temperature of the PNSPE film confirming the thermally activated dielectric and electrical behaviour of the electrolyte material. The temperature dependent de ionic conductivity and relaxation times of the PNSPE film obey the Arrhenius behaviour of their activation energy values around 0.3 eV. Dielectric parameters reveal that the ions transportation and ionic conductivity in solid ion-dipolar complexes of the PNSPE films are governed by the values of dielectric permittivity and the relaxation times corresponding to structural dynamics. Results of this study infer that the ultrasonic-microwave irradiation processing used during the sample preparation enhances the dielectric permittivity, structural dynamics and ionic conductivity of the PNSPE film as compared to that of the classical solution-cast method prepared film. The ionic conductivity values of these PNSPE films at ambient temperature are found of the order of 10(-5) S cm(-1) which confirms them as promising electrolyte materials for lithium ion battery and also for all-solidstate ion conducting device applications. 

Polymer blend; Solid polymer electrolyte; Dielectric permittivity; Relaxation time; Ionic conductivity