Conductivity, dielectric studies and structural properties of P(VA-co-PE) and its application in dye sensitized solar cell

Poly(vinyl alcohol-co-ethylene), P(VA-co-PE) gel polymer electrolytes (GPEs) with sodium iodide (NaI) as a dopant salt was synthesized and investigated. Electrolytes containing different concentrations of NaI salt were studied using AC impedance spectroscopy, FTIR spectroscopy, and XRD spectroscopy. The results from dielectric studies reveal both the real part and imaginary part of complex permittivity decrease with increasing frequency. An opposite trend was observed when the temperatures of the samples were increased. Besides, the dispersion relation from the modulus studies confirmed that ionic conductivity is dominant in the GPE samples. Results from temperature studies reveal that all GPE samples conform the Arrhenius equation in the temperature range of 303 K to 373 K. The sample with 40% of NaI exhibits the highest ionic conductivity of 2.266 mS cm−1 with the activation energy of 0.16808 eV. Furthermore, FTIR studies proved the complexation between P(VA-co-PE) and NaI. The crystallinity of the samples was shown to be increasing with the increasing concentration of NaI salt via XRD results. Finally, DSSCs were assembled using the polymer electrolyte and used for photovoltaic studies. The best performance of DSSC was obtained with the energy conversion efficiency of 3.32% using the GPE sample with 40% NaI.