Solid polymer nanocomposite electrolyte complexes PEO/PVP/NaIO4 with TÌO2 nano-additives: Na+ ion conductivity and dielectric studies

The effects of TÌO2 nano-additives on electrical conductivity and dielectric properties of the nanocomposite solid polymer electrolyte (NCSPE) system PEO/PVP/NaIO4/TiO2 were investigated in order to asses its competence for ion-electrolytic applications. The examined NCSPEs for sodium-ion conduction were based on binary polymer blend formed from poly(ethylene oxide) (PEO) and polyvinyl pyrrolidone (PVP), with added sodium metaperiodate (NaIO4) at concentration of 10 wt.% [1,2] and nanoparticles of Titanium oxide (TiO2) of average size ~ 10 nm. TiO2 was included at concentrations 1, 2, 3, 4 and 5 wt.%. As depending on the concentration of TiO2 nanoparticles, the electrical conductivities and dielectric properties of thin films (150 μm thick) of the salt-complexed polymer-ion NCSPE PEO/PVP/NaIO4/TiO2 were studied by complex electrical impedance and dielectric spectroscopy in the frequency range 1 Hz - 1 MHz. Compared to additive-free samples, the incorporation of nano-sized TiO2 into the PEO/PVP polymer matrix increased both electrical conductivity and dielectric permittivity of PEO/PVP/NaIO4/TiO2 NCSPEs by more than one order of magnitude at concentration 3 wt.% of TiO2 . The results from dielectric analysis were related to the macroscopic properties of the examined ion-conductive NCSPEs and show their ability for Na+ ion-conducting applications.