Zeolitic inorganic-organic polymer electrolyte based on oligo(ethylene glycol) 600 K2PdCl4 and K3Co(CN)6

Acqueous solutions of K2PdCl4 and K3Co(CN)(6) were combined separately with PEG600 and then reacted together, giving rise to a sol --> gel transition followed by a gel --> plastic transition. This reaction scheme produced a new zeolitic inorganic-organic polymer electrolyte, {CoxPdy(CN)(z)Cl-v(CH2nH4n+2On+ 1)K-l] Rheological investigations carried out by a dynamic oscillatory method demonstrated that the sol - gel transition is strongly affected by temperature. Indeed, the gelation process produced the most robust solid gel structure in the shortest time when conducted at elevated temperatures. TG measurements demonstrated that the synthesized polymer electrolyte is thermally stable up to ca. 210 degreesC. Scanning electronic microscopy showed that the material consists of a compact granular paste. On the basis of mid and far Fourier transform infrared spectroscopy and analytical data, it was concluded that the synthesized material is a zeolitic inorganic-organic network where CN bridges bond together Co and Pd atoms and PEG600 bridges Pd atoms. Conductivity of the product was investigated by impedance spectroscopy in the temperature and frequency ranges of 20-80 degreesC and 20 Hz to 1 MHz, respectively; results demostrated that the polymer electrolyte conducts ionically by two distinct conductivity regions which follow Arrhenius type equations. At 25 degreesC the conductivity of the material is on the order of 3 x 10(-5) S cm(-1). A mechanism based on the jump relaxation model is proposed to explain the conductivity of the polymer.