Ion dynamics behavior in solid polymer electrolyte

Abstract

Abstract A conducting polymer system, having room temperature conductivity ~ 1.26 × 10 − 4 S/cm (for 50% NaI concentration) and ionic transference number ~ 0.80, has been prepared by mixing NaI in a novel polymer host (synthesized polymer + poly (ethylene oxide)). Mobility ( μ ) and total number of charge carriers ( N ), estimated from dielectric parameters, have a value of ~ 1.65 × 10 − 2 cm 2 V − 1 s − 1 and 4.70 × 10 16 cm − 3 respectively. Inverse relationship between conductivity power law exponent n and N / N 0 (fractional number of dissociated charge carriers) is explained in terms of statistical nature of ion dynamics. The temperature dependence of “ n ” studied separately in universal power law (UPL) and super linear power law (SLPL) region revealed that exponent n responds differently to temperature in these two different regions. Ion hopping frequency ( ω p ), obtained from universal power law (UPL) region, is used for scaling of conductivity and permittivity curves. Conductivity scaling followed a master curve Y = 1 + X n , having n = 0.85 ± 0.07, covering both UPL as well as SLPL region which confirms that both phenomena have the same origin.