Conductivity, thermal stability and morphology of a new Z-IOPE inorganic-organic network with the formula [FexSny(CH3)2y(CN)zClv(CH2nH4n+2On+1)Kl]

This paper reports accurate studies on the morphology, thermal stability and electrical spectroscopy of a zeolitic inorganic-organic polymer electrolyte (Z-IOPE) with the formula [FexSny(CH3)2y(CN)zCly(C2nH4n+2On+1)Kl]. This material was prepared by means of a sol-gel process. A possible mechanism of the sol-gel process is proposed. Scanning electron microscopy showed that the Z-IOPE resembles a gummy paste with a rough texture and grains on the surface of the bulk material. Thermogravimetric investigations indicated that the material is thermally stable up to approximately 200°C. A detailed study of the mechanism of ion conduction in this system was carried out using impedance spectroscopy in the 20 Hz to 1 MHz range. The analysis of real and imaginary components of conductivity spectra indicated that a full characterization of the AC electrical response for this Z-IOPE system requires an equivalent circuit analysis for frequencies lower than 10 kHz and correlated ionic motion analysis based on the Universal Power Law for frequencies higher than 10 kHz. These studies demonstrated that the Z-IOPE material conducts ionically by a mechanism mainly regulated by segmental motion of the host material, and that charge migration by ion hopping between equivalent coordination sites is not to be completely excluded in the host network. Finally, the conductivity of 4.77 x 10-5 S/cm at 25°C