Sustainable tri polymer solid electrolytes from ghatti and xanthan gums for energy storage applications

This work explores a solid polymer electrolyte (SPE) system prepared from bio-sourced polysaccharides (Ghatti gum and Xanthan gum) blended with a biodegradable synthetic polymer Polyvinyl alcohol (PVA). The films were fabricated using a solution casting technique and characterized to assess their structural, thermal, and electrochemical properties. X-ray diffraction (XRD) confirms an increased amorphous fraction in the optimized composition (GXP5), while Fourier transform infrared spectroscopy (FTIR) reveals strong hydrogen bonding interactions among the polymers. Differential scanning calorimetry (DSC) shows a rise in glass transition temperature to 88.4 °C in GXP5, indicating enhanced chain rigidity. Surface morphology is observed through scanning electron microscopy (SEM) which is uniform and defect-free. AC Impedance studies demonstrate that GXP5 exhibits optimal performance with a maximum conductivity of 1.19 × 10⁻⁷Scm⁻¹ at ambient temperature. Dielectric analysis suggests non-Debye-type relaxation behavior and efficient ion transport. A symmetric supercapacitor device using the GXP5 electrolyte is fabricated and it displays favorable capacitive performance, confirming its suitability for electrochemical applications. These results highlight the potential of biopolymer-based tri-polymer blends as sustainable and effective electrolyte materials for energy storage devices.