Characterization of MMT and OMMT Nanofillers Effect on the Optical, Dielectric, Electrical, and Electrochemical Properties of PEO/PMMA/P(VDF-HFP)/LiTFSI Solid Polymer Electrolytes

Equal weight percentage compositional ratio poly(ethylene oxide) (PEO)/poly(methyl methacrylate) (PMMA)/poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) ternary polymer blend as host matrix with 35 wt% lithium bis(trifluoromethane sulfonyl)imide (LiTFSI) salt based solid polymer electrolyte (SPE), and the same electrolyte composition with 5 wt% montmorillonite (MMT) and also organomodified-MMT (OMMT) clay nanofiller based nanocomposite-SPEs (NSPEs) are prepared through the solution casting method. The differential thermograms confirm that these SPE and NSPE films are amorphous. The ultraviolet-visible wavelength range absorbance study and analysis of Tauc plots explained the wide bandgap semiconducting behavior of these electrolyte materials. The formation of ion-dipole complexes, involved dielectric polarization processes in high dielectric permittivity values, and structural dynamics in the SPE and NSPE films are characterized by 20 Hz to 1 GHz broadband range dielectric measurements, at 27°C. The complex impedance, electrochemical window stability (EWS) voltage, ion transference number (tion), and reversibility and cyclability performance of these electrolyte materials are examined. The optimum values of dc ionic conductivity (~10−6 S/cm), electrochemical performance (EWS ~6 V and tion ~0.84), and optical properties (bandgap Edg ~3.6 eV) of these electrolyte materials credited their potential uses in advances of energy storage, optoelectronic, and iontronic devices.