Ion dynamics in NaBF4 salt-complexed PVC–PEO blend polymer electrolytes: correlation between average ion hopping length and network structure

• DOI: 10.1007/s11581-017-2154-2
• Publication Date: 2017-05-29T23:27:49Z
• Authors: Anirban Roy; Bula Dutta; Subhratanu Bhatta...
• Keywords: 01 natural sciences; 0104 chemical sciences; 3. Good health

Electrical transport properties of a series of NaBF4 salt-doped PVC–polyethylene oxide blend polymer electrolytes are studied using impedance spectroscopy. X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry are implemented to characterize the structural properties of the electrolytes. The characterization data clearly indicate that the interaction between the dopant salt and the polymer host substantially influences the overall crystallinity of the electrolytes. Experimental frequency-dependent complex conductivity and loss tangent data are analyzed using a physical model to extract separately the mobile ion concentration and ion mobility of the charge carriers and the type of their thermal activation. The average hopping length of free ions, which essentially controls the macroscopic ion transport within the electrolytes, is found to be strongly correlated to the network structure of the electrolytes. Both the dc conductivity and free ion mobility are observed to be strongly coupled with the segmental dynamics of blend polymer host over the entire range of ion content studied.