Characterization of un-plasticized and propylene carbonate plasticized carboxymethyl cellulose doped ammonium chloride solid biopolymer electrolytes

•Characterization of un-plasticized and propylene carbonate plasticized carboxymethyl cellulose doped with ammonium chloride solid biopolymer electrolyte.•The enhancement of ionic conductivity for plasticized SBE compared to un-plasticized SBE.•The plasticized SBE had increased the decomposition temperature compared to un-plasticized SBE.•IR spectra were compared by using 2 methods (experimental and computational)—FTIR spectroscopy and Gaussian software.

Two solid biopolymer electrolytes (SBEs) systems of carboxymethyl cellulose doped ammonium chloride (CMC-AC) and propylene carbonate plasticized (CMC-AC-PC) were prepared via solution casting technique. The ionic conductivity of SBEs were analyzed using electrical impedance spectroscopy (EIS) in the frequency range of 50 Hz–1 MHz at ambient temperature (303 K). The highest ionic conductivity of CMC-AC SBE is 1.43 × 10−3 S/cm for 16 wt.% of AC while the highest conductivity of plasticized SBE system is 1.01 × 10−2 S/cm when added with 8 wt.% of PC. TGA/DSC showed that the addition of PC had increased the decomposition temperature compared of CMC-AC SBE. Fourier transform infrared (FTIR) spectra showed the occurrence of complexation between the SBE components and it is proved successfully executed by Gaussian software. X-ray diffraction (XRD) indicated that amorphous nature of SBEs. It is believed that the PC is one of the most promising plasticizer to enhance the ionic conductivity and performance for SBE system.