Enhancement of Dielectric Energy Storage of PVDF‐Based Composites With 2D Sheet‐Like MOFs

ABSTRACT In this study, MIL‐53(Ni)‐TCPP, doped with Tetra‐carboxyphenyl porphyrin (TCPP), was successfully prepared via a hydrothermal method, and polyvinylidene fluoride (PVDF) composite films were manufactured using a pouring technique. The inclusion of porphyrin enhances the electronic storage capability of MIL‐53(Ni), empowering it to function as micro‐capacitive elements within the PVDF matrix. Consequently, this augmentation leads to an advancement in the dielectric characteristics of the blended films. Additionally, the MIL‐53(Ni)‐TCPP can retard electron motion and slow down the extension of electrical trees; consequently, this elevates the strength of the breakdown field in the hybrid films. The findings indicated that when the composite film incorporates 0.4 wt% of 2D MIL‐53(Ni)‐TCPP nanosheets, it achieved a notably elevated dielectric constant (~12.13) at 1 kHz and high breakdown field strength (~260 kV/mm). This represents an approximately 24% increase in dielectric constant when compared with PVDF film (~9.75) and about a 29% increase in breakdown field strength (~202 kV/mm), while the dielectric loss remains comparatively low (~0.046). When the field strength is at its peak, the energy storage density (~5.34 J/cm 3 ) experiences an augmentation of 212.3% in comparison to that of neat PVDF film (~1.71 J/cm 3 ). This study offers a viable approach to obtaining polymer‐based composites with high energy storage capacities.