MXene/PVDF metacomposites with ultra-high and negative permittivity

The dielectric behavior of MXene/polyvinylidene fluoride (PVDF) metacomposites, which simultaneously exhibit ultra-high dielectric constants and negative permittivity, has been investigated. The material exhibits a substantial enhancement in dielectric constant at low frequencies, with values reaching 10 5 , which is primarily caused by interfacial polarization and the unique architecture of MXene. The composite transitions to negative permittivity with increasing MXene content, a result of conductive network formation and free electron accumulation at high filler levels. The dielectric response is highly morphology-dependent, with accordion-shaped formations producing Drude-type negative permittivity and clay-like formations showing Lorentz-type negative permittivity. These dual characteristics of ultra-high and negative permittivity make MXene/PVDF metacomposites highly promising for applications in advanced electronic devices, energy storage, and electromagnetic wave manipulation.