Tailoring the electrical characteristics of poly(vinylidene fluoride) hybrid composites incorporating the metal organic framework HKUST-1 and nanoconfined [Bmim]2[NiCl4] ionic liquid

This study reports ternary hybrid composites based on a poly(vinylidene fluoride) (PVDF) polymer matrix incorporating metal-organic framework (MOF) microparticles (HKUST-1), and an ionic liquid (IL) (bis(1-butyl-3-methylimidazolium) tetrachloronickelate ([Bmim] 2 [NiCl 4 ])), the pores of HKUST-1 being filled with the IL to tune the composite's electrical response. It is shown that introducing MOF and IL separately promotes nucleation of the electroactive phase of the polymer. However, the electroactive phase content of the PVDF/HKUST/IL composite lies between that of the MOF and IL composites. In IL-containing composites, the dielectric response is dominated by interfacial polarization and a conductivity-related peak, which mask the β -relaxation. The distribution of IL throughout the PVDF matrix and at the MOF-polymer interfaces causes the PVDF/HKUST/IL hybrid composite to display intermediate conductivity values between those of the PVDF/HKUST and PVDF/IL systems. While the IL dispersed within the PVDF matrix promotes ion transport and enhances conductivity, the IL located at the MOF-polymer interfaces may experience partial confinement or limited mobility. This dual-confinement effect allows for the precise "tuning" of conductivity and dielectric relaxation. The tailoring of electrical characteristics of these ternary composites provides a pathway for the development of electroactive materials suitable for a wide range of application requirements. • Synergetic effect of IL-laden MOF composites in a poly(vinylidene fluoride) polymer matrix is studied. • Polymer phase, thermal properties and dielectric relaxation spectra are evaluated for this nanocomposite. • The inclusion of these fillers affects the nucleation of crystalline phases • The IL filler is the main responsible by the conductivity behavior of the PVDF polymer. • The developed nanocomposite composites show suitable electrical properties for a variety of applications.