Effect of methyl red dye on dielectric and conductivity properties of PEO/CdCl₂ electrolytes

In this report the conductivity and dielectric properties of polyethylene oxide-cadmium chloride (PEO/CdCl₂) polymer electrolyte films doped with an azo dye methyl red (MR) are discussed. The films were prepared by solution casting technique at different concentrations of the dye in PEO/CdCl₂ electrolyte. The thermal behavior, chemical interaction of the dye with the electrolyte and surface morphology were studied by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) respectively. The conductivity and dielectric properties were measured as a function of composition and temperature using complex impedance spectroscopy. The temperature dependent electrical conductivity of the films exhibited Arrhenius type behavior. Conductivity and dielectric results also signify the enhancement in the amorphous phase of the polymer electrolyte dye systems. The value of highest conductivity observed is 1.21x10⁻⁴ at 343K and the conductivity of the film was enhanced by a three orders of magnitude.