Thermal and electrical properties of PEO9 CuCNS : Al2O3 nano-composite polymer electrolyte

Abstract

Nano-composite polymer electrolyte films of composition PEO9 CuCNS + 10 wt% Al2O3 were prepared by solvent casting technique. DSC traces show that the composite electrolyte exhibits a pronounced crystalline to amorphous phase transition around similar to 60 degrees C similar to the filler-free electrolyte. The conductivity variation with temperature for both the filler free (PEO)(9)CuCNS material and composite polymer electrolyte (PEO)(9) CuCNS + 10 wt% Al2O3 shows Arrhenius behaviour exhibiting two distinctive regions below and above similar to 60 degrees C. There is about two-fold increase in the overall electrical conductivity of the composite polymer electrolyte compared to the filler free polymer electrolyte. DC Polarization measurements indicate that the charge transport in this electrolyte is predominantly due to ions, both systems exhibiting high anionic transference numbers : t(-) = 0.86 for (PEO)(9) CuCNS, and t(-) = 0.98 for (PEO)(9)CuCNS + 10 wt %, Al2O3. The observed conductivity enhancement is very likely to be due to the creation of additional transient sites and conducting pathways for the migrating anions caused by Lewis acid-base type H-bonding with OH surface groups on filler grains.