High performance poly(ethylene‐co‐vinyl acetate)/nickel oxide nanocomposite prepared through open mill mixing technique for energy storage applications.

Highlights Polymer nanocomposite films of poly(ethylene‐co‐vinyl acetate) (EVA) with different concentrations of nickel oxide (NiO) nanoparticles (NPs), produced by an open two‐roll mill mixing method. Structural characterization using Fourier transform infrared (FTIR), UV–visible spectroscopic studies and x‐ray diffraction (XRD) analysis showed elevated peak intensity for composites confirming good polymer‐filler interaction, optical clarity and improved crystallinity. Morphological analysis by field emission scanning electron microscopy (FE‐SEM) and high‐resolution transmission electron microscopy (HR‐TEM) revealed the structural regularity of nanocomposites (NCs). Augmented thermal stability, evident from thermogravimetric analysis (TGA) with increased decomposition temperature was corroborated by an increase in glass transition temperature (Tg) detected through differential scanning calorimetry (DSC) analysis. Dielectric constant and alternating current (AC) conductivity values increased with temperature, filler content and frequency. Composites containing 7 wt% NiO showed significant enhancements in mechanical properties compared to EVA, with tensile strength increasing by 122%, tear strength by 179.9%, and impact strength by 111.9%. EVA/10 wt% NiO composite exhibited the highest hardness increase of 11.9%, while elongation at break decreased by 8% for the same composition. The experimental results suggest that EVA/NiO nanocomposite films can be employed as promising alternatives for flexible dielectric substrates for optoelectronic devices. A series of EVA/NiO NCs were prepared and characterized. Enhanced optical property, thermal stability and Tg. Possess excellent electrical properties. Mechanical strength and impact resistance of EVA was greatly enhanced. A promising material for flexible energy storage applications. [ABSTRACT FROM AUTHOR]