ABSTRACT

Lithium (Li⁺) ion conducting nanocomposite polymer blend electrolytes (NCPBEs) based on poly(ethylene oxide) (PEO), poly(vinylidene fluoride hexafluoropropylene) (P(VdF-HFP)) as polymer hosts, lithium perchlorate (LiClO₄) as an electrolyte and strontium titanate (SrTiO₃) as a nanofiller have been prepared by both the conventional stirring and ultrasonic irradiation methods. Complex formation and hence the structural changes of the prepared samples have been confirmed by X-ray diffraction analysis. Conductivity studies have been carried out by means of AC impedance spectroscopy. In order to highlight the role of ultrasonic irradiation, conductivity values have been compared with the values obtained through conventional mechanical stirring method. It has been found that the system with 15 minutes of ultrasonic irradiation resulted in better homogenous dispersion of SrTiO₃ in PEO/P(VDF-HFP)/LiClO₄ matrix. Maximum ionic conductivity of 2.519 × 10⁻⁴ Scm⁻¹ has been obtained for 6 wt% of SrTiO₃ system which is a magnitude higher than the ionic conductivity value, 2.031 × 10⁻⁵ Scm⁻¹ obtained for the original NCPBE prepared using conventional mechanical stirring at room temperature. Further, ionic conductivity value increases with the increase of temperature and it exhibit the Arrhenius relation. Higher degree of free ionic motion in the samples has been proven by the increase in intensity of photoluminescence spectra peaks. The dielectric properties of the prepared samples have also been studied using the complex dielectric permittivity spectra and complex electric modulus spectra. The morphology and hence the surface roughness of the samples have been depicted through AFM study.

摘要

基于聚环氧乙烷（PEO）的锂（Li ⁺）离子导电纳米复合聚合物共混电解质（NCPBE），作为聚合物主体的聚偏二氟乙烯六氟丙烯（P（VdF-HFP）），高氯酸锂（LiClO ₄）电解质和钛酸锶（SrTiO ₃通过常规的搅拌和超声辐射方法已经制备了作为纳米填料的）。通过X射线衍射分析证实了复合物的形成以及由此制备的样品的结构变化。电导率研究已经通过交流阻抗谱进行。为了突出超声波辐射的作用，已将电导率值与通过常规机械搅拌方法获得的值进行了比较。已经发现，用15分钟的超声辐射的系统导致SrTiO ₃在PEO / P（VD​​F-HFP）/ LiClO ₄基质中更好的均匀分散。对于6 wt％的SrTiO，获得的最大离子电导率为2.519×10 ^-4 Scm ^-1₃系统比离子电导率值高的幅度，2.031×10 ^-5 SCM ^-1使用常规机械搅拌在室温下制备的原始NCPBE获得。此外，离子电导率值随温度的升高而增加，并且表现出阿伦尼乌斯（Arrhenius）关系。样品中较高的自由离子运动程度已通过光致发光光谱峰强度的增加得到证明。还使用复介电常数谱和复电模量谱研究了制备样品的介电性能。通过AFM研究已经描绘出样品的形态和表面粗糙度。