SAXS/WAXS/DSC Study of Temperature Evolution in Nanopolymer Electrolyte

TL;DR

This study investigates the temperature-dependent nanostructure and phase transitions of PEO-based nanopolymer electrolytes and nanocomposites using SAXS, WAXS, and DSC, revealing insights into their thermal behavior and conductivity enhancements.

Contribution

It provides a comprehensive analysis of how TiO2 nanograins influence the nanostructure and thermal properties of PEO electrolytes through combined SAXS, WAXS, and DSC measurements.

Findings

Nanocomposites show increased conductivity above 65°C.

Temperature affects nanograin structure and crystallization.

Melting and crystallization temperatures of nanograins are identified.

Abstract

Electrolytes as nanostructured materials are very attractive for batteries or other types of electronic devices. (PEO)8ZnCl2 polymer electrolytes and nanocomposites (PEO)8ZnCl2/TiO2 were prepared from PEO and ZnCl2 and with addition of TiO2 nanograins. The influence of TiO2 nanograins was studied by small-angle X-ray scattering (SAXS) simultaneously recorded with wide-angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) at the synchrotron ELETTRA. It was shown by previous impedance spectroscopy (IS) that the room temperature conductivity of nanocomposite polymer electrolyte increased more than two times above 65oC, relative to pure composites of PEO and salts. The SAXS/DSC measurements yielded insight into the temperature-dependent changes of the grains of the electrolyte as well as to differences due to different heating and cooling rates. The crystal structure and temperatures of melting and crystallization of the nanosize grains was revealed by the simultaneous WAXS measurements.