Absorbance, Transmittance and Optical Energy Band Gap Studies of TSP: NaNO3 Based Polymer Electrolyte

Abstract

Solid bio-polymer electrolyte (SBPE) material film was synthesized from (TSP) Tamarind Seed Polysaccharide is doped with salt sodium nitrate (NaNO₃) by solution cast method. Energy band gap studies were observed from UV- visible absorption spectroscopy between 220nm-820nm. Optical transmittance, optical conductance is determined from optical absorption. The optical energy band gap is found from these optical parameters. Optical energy band gap changes from 5.01eV to 4.6 eV for various concentrations of TSP: NaNO₃. Some of the optical parameters like indirect bandgap and direct band gaps are extremely high and by increasing the dopant salt concertation to host polymer then these parameters are decreased gradually. Finally, the optical band gap of energy had obtained very low value for 70% TSP: 30% NaNO₃.