Effect of ZnS Dispersoid in Structural and Electrical Properties of Plasticized CA-NH4I

Plasticized solid polymer electrolytes compose of cellulose acetate (CA) host polymer, ammonium iodide (NH4I) salt, propylene carbonate (PC) plasticizer were prepared by solution cast technique. The highest room temperature ionic conductivity (1.17 × 10-4 S cm-1) was achieved for sample with composition of CA: 25 wt. % NH4I: 40 wt. % PC. The addition of zinc sulfide (ZnS) dispersoid ceramic filler to the highest conductivity of plasticized CA-NH4I system enhanced the ionic conductivity up to 6.24 × 10-4 S cm-1 at room temperature. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy confirmed the complexation between polymer and salt. The disruption of the crystalline peaks of ZnS and NH4I on the X-ray diffraction (XRD) pattern of CA-NH4I, plasticized CA-NH4I and composited CA-NH4I-PC established the complexation between polymer and salt were takes place and reduce the crystallinity of the samples and hence increasing in ionic conductivity. The transference number suggested that the charge transport is predominantly due to ions.