Impact of electron irradiation on microstructural, dielectric and electrical properties of potassium ion conducting PVA solid polymer composite

The study investigates the solid polymer composite (SPC) made using solution casting with PVA as the host polymer and KI as the dopant. The SPC was exposed to electron beam doses ranging from 0 to 300 kGy to study its microstructural, optical, thermal, electrical, and dielectric properties. XRD, FTIR, and TGA were used to study the structural and thermal properties. Results showed variations in crystalline phase, charge transfer complex formation, and defects due to crosslinking and chain scission processes. The activation energy for thermal decomposition values matches the onset temperature. UV–Vis studies revealed changes in optical properties with radiation dose, attributed to molecular ordering changes, defects formation, and charge transfer complexes. Electric and dielectric properties were studied using impedance spectroscopy. The highest ac conductivity was achieved for 300 kGy-irradiated SPC, attributed to free radical production. The correlated barrier hopping model was found to be the best fit for characterizing the electrical conduction mechanism of the system. Dielectric measurements revealed non-Debye behavior and substantial dielectric dispersion in the frequency range, increasing with irradiation dose. The results suggest the SPC is a potential candidate for solid-state energy storage and conversion applications.