Enhanced physical, electrical, and structural properties of chitosan thin films doped with Ag@ZnO nanoparticles for energy storage applications

Chitosan thin films doped with varying concentrations (0, 2, 5, 7, and 10 %) of silver-doped zinc oxide (Ag@ZnO) nanoparticles (NPs) were synthesized using the Solution Casting method. Analyses revealed that increased doping enhanced the films’ physical, electrical, and structural properties. X-ray diffraction (XRD) confirmed the wurtzite hexagonal structure of Ag@ZnO NPs. Photoluminescence showed charge transfer between chitosan and NPs, with emissions in the blue and violet ranges. UV–VIS spectroscopy indicated improved barrier effects, while Tauc plot analysis showed a decrease in the band gap with higher doping. Fourier-transform infrared (FT-IR) analysis confirmed strong interactions between chitosan and nanoparticles. Impedance testing demonstrated increased conductivity with higher Ag@ZnO NP concentrations. These results suggest that doping chitosan films with Ag@ZnO NPs effectively modulates impedance and conductivity while maintaining flexibility, making them suitable for efficient electrolyte separators in supercapacitors.