Hybrid GO/TiO2 nanoparticles reinforced NaAlg/PVA blend: Nanocomposites for high‐performance energy storage devices

Abstract In this study, novel flexible polymer nanocomposite films formed of polyvinyl alcohol (PVA), sodium alginate (NaAlg), titanium dioxide (TiO2) and graphene oxide (GO) as nanofiller are fabricated by using casting method. The PVA/NaAlg‐GO/TiO 2 nanocomposite films are characterized using various techniques. The synergistic effects of GO/TiO 2 on the electrical, dielectric properties, and the energy density efficiency of PVA/NaAlg blend have been investigated in the range of frequency from 10 Hz to 7 MHz. The XRD data showed that the intensity of the PVA/NaAlg‐GO/TiO 2 nanocomposites films decrease with nanofiller concentration. The FTIR spectroscopy provides proof that the complex formed. The optical studies were carried out using UV–Vis. spectroscopy. The energy bandgap values of PVA/NaAlg‐GO/TiO 2 nanocomposite films were calculated using Tauc's plot. It is shown that the host matrix's E g value decreases from 4.97 to 4.29 eV for direct transitions and from 4.37 to 2.29 eV for indirect transitions. The electrical and dielectric parameters of the nanocomposites showed that the maximum electrical properties were observed for the composite with 8 wt% loading of GO/TiO 2 . The σ dc increased from 2.45 × 10 −9 to 5.02 × 10 −7 S cm −1 . In addition, frequency exponent S decreased from 0.82 to 0.54. These findings demonstrated that there are significant modifications in the fabricated samples, which open the road for utilizing the PVA/NaAlg‐GO/TiO 2 nanocomposite as flexible films for solar cells and electrical energy storage applications.