Thermolysis and Conductivity Studies of Poly(Ethylene Oxide) (PEO) Based Polymer Electrolytes Doped with Carbon Nanotube

TLDR

Solid polymer electrolytes of PEO were prepared by solution casting and characterized by DSC, impedance spectroscopy, and TGA. Adding LiPF6, EC, and αCNT lowered the PEO melting peak from 69 °C to 61 °C, increased conductivity to 10⁻³ S cm⁻¹ at 5 wt % αCNT, and altered thermal stability, with distinct behavior above and below 100 °C.

Abstract

In this research, solution-casting technique was employed for the preparation of solid polymer electrolytes poly(ethylene oxide) (PEO) films were characterized via differential scanning calorimetry (DSC), impedance spectroscopy (IS) and Thermogravimetric (TGA). With addition of varies of lithium hexaflurote (LiPF6), ethylene carbonate (EC) and amorphous carbon nanotube (αCNT), the endothermic peack continuously decrease from 69 to 61°C. The conductivity values for PEO complexes increased continuously and reached a maximum of 10-3 Scm-1 when 5wy% αCNTs was added into the PEO complexes. Thermogravimetric analysis (TGA) results showed that the amount of LiPF6, EC and has a significant effect on the thermal stability of polymer complexes. The TGA curves also indicated that the thermal behaviour of composites polymer electrolytes differs significantly between low temperature (> 100 °C) and high temperature (200 °C) range.