Electrochemical Study of PW12O$rm{_{40}^{3-}}$ in Poly(ethylene glycol) Electrolyte

The electrochemical properties of PW₁₂O (abbreviated as PW₁₂) anion in poly(ethylene glycol) (PEG) have been studied by cyclic voltammetry, complex impedance and FT‐IR spectroscopy. The PW₁₂ anion in PEG‐LiClO₄ electrolyte shows reasonable facile electrochemistry, and the diffusion coefficients of PW₁₂ were measured with microelectrode. It is shown that ionic conductivity of polymer electrolytes based on low molecular weight PEG can be improved by the addition of PW₁₂. The increase of conductivity is coupled with decrease of transient cross‐links density of polymer chains which is evidenced by the downshift of C? O? C stretching mode. The phenomena are explained in view of ion‐ion and ion‐polymer interactions.