Conductive V2C MXene and paralelectric SrTiO3 containing polymer composites with high dielectric constant

Strontium titanate (STO) is a ferroelectric ceramic that shows paraelectric behaviour at room temperature , leading to a low dielectric constant in polymer composites with STO particles for energy storage applications. In this study, to improve the dielectric constant of polymer/STO composites, STO filler was modified via its hybridisation with conductive V 2 C MXene to form high-polarity interphase. The high-polarity mechanism of the V 2 C/STO interphase was analysed using density functional theory (DFT) calculations. An interesting connection between V 2 C and STO through an interfacial single oxygen atom was observed. Polymer composites containing hybrid filler exhibited balanced electrical properties, including a high dielectric constant, low tanδ, and high breakdown strength . The novelty of this study lies in the strategy of improving the dielectric response of a paraelectric ceramic filler through heterojunction modification. Consequently, the composite with 9 wt% hybrid filler exhibited a high dielectric constant of ~87 and low tanδ of ~0.038 at 100 Hz along with a reasonably high breakdown strength of ~233 MV/m. It is expected that this study will contribute to the effective design of high-polarity hybrid ceramic fillers for advanced composite dielectric applications.