MXene/SrTiO3/PVDF ternary composites with excellent dielectric properties and thermal stability

As the demand for lightweight and compact integrated devices accelerates, dielectric materials are pivotal in enabling efficient energy storage. Composite materials, particularly those combining a polymer matrix with two-dimensional (2D) conductive MXene fillers, have emerged as promising candidates for improving dielectric performance. However, their high dielectric constant is often accompanied by significant dielectric loss, limiting their application in high-frequency circuits and electronic devices. This study investigates a ternary composite system consisting of polyvinylidene fluoride (PVDF) as the matrix, Ti 3 C 2 T x MXene as a conductive filler, and strontium titanate (SrTiO 3 ) as a ceramic filler to enhance dielectric properties. The ternary composites were prepared through a combination of physical mixing followed by a hot-pressing process. The results demonstrate that the MXene/SrTiO 3 /PVDF composites achieve a notable reduction in dielectric loss while retaining a high dielectric constant. At 12 wt% MXene, the composite achieves a dielectric constant of 117.8 at 10 3  Hz, 14.7 times higher than pure PVDF, with dielectric loss reduced by 71.4% compared to MXene/PVDF composites. Furthermore, the incorporation of SrTiO 3 markedly enhances the thermal stability, elevating the thermal decomposition temperature of the composite to 437.88 °C, up from 357.9 °C for pure PVDF. This research presents a promising strategy for developing capacitors with superior dielectric properties and enhanced thermal stability, suitable for high-temperature applications.