WITHDRAWN: PVA + NaSCN and ionic liquid based polymer electrolyte for supercapacitor

Abstract In this study, solid flexible polymer electrolyte films composed of polyvinyl alcohol (PVA) and sodium thiocyanate (NaSCN) have been prepared using the solution cast technique. For further enhancement in ionic conductivity, an ionic liquid (IL) 1-ethyl-3-methyl-imidazolium tricyanomethanide ([EMIM][TCM]) has been doped into polymer-salt complex system (PVA+NaSCN). Ionic liquid doped gel polymer electrolyte films (GPEs) have been characterized using X-Ray Diffraction (XRD), Polarized optical microscopy (POM), Fourier Transform Infrared Spectroscopy (FTIR) and conductivity measurements. The XRD is done to check the degree of crystallinity, amorphicity of ionic liquid doped polymer electrolyte films, and amorphicity of GPEs further increases with increasing content of IL. The POM assesses the changes in the surface morphology due to inclusion of salt and ionic liquid in PVA. The compositional nature of GPE films is checked using FT-IR studies. The electrical and electrochemical properties are characterized using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques. The maximum conductivity value for the GPE film is achieved 1.05×10-5 S cm-1 for 6 wt% of IL in polymer-salt complex. The ionic transference number (tion) is found to be 0.97. A laboratory scale electrical double-layer capacitor (EDLC) has been fabricated using optimized GPE films. The specific capacitance value is found to be 3 F g-1 calculated using cyclic voltammogram of EDLC cells.