Relative role of plasticizer and nano size fumed silica on the conductivity behaviour of PEO-NH₄PF₆polymer electrolytes

Abstract

The conductivity of proton conducting polymer electrolytes obtained by the complexation of ammonium hexafluorophosphate (NH₄PF₆) with polyethylene oxide (PEO) increases with the addition of propylene carbonate (PC) (plasticized polymer electrolyte) and nano size fumed silica (nano composite polymer electrolytes). Plasticized polymer electrolytes have higher conductivity whereas nanocomposite polymer electrolytes have better mechanical properties. The simultaneous addition of PC and fumed silica leads to the formation of electrolytes with higher conductivity (4.50<img src='/image/spc_char/cross.gif' border=0>10^-5 S/cm at 25^oC) as well as better mechanical strength. The curved nature of log conductivity versus reciprocal temperature plot suggests the amorphous nature of these electrolytes and a small change in conductivity observed over the 20^oC to 100^oC temperature range is also suitable for their use in applications.