Significantly enhanced electrostatic energy storage performance of P(VDF-HFP)/BaTiO₃-Bi(Li_0.5Nb_0.5)O₃ nanocomposites

Microelectronics and electrical power systems require dielectric polymer-based dielectrics with high energy density that are simple to process. However, the currently available polymer-based dielectric materials require demanding process conditions and relatively low energy density. Herein, we propose P(VDF-HFP)-based nanocomposite by a simple and practical mechanical method based on a combination of solid phase reaction and sieving to prepare 0.88BaTiO₃-0.12Bi(Li_0.5Nb_0.5)O₃ nanoparticles (BT-BLN nps). The experimental and simulation result verify that the BT-BLN nps significantly improve the breakdown strength and energy storage performance of dielectric materials. Remarkably, the highest discharge energy density of the BT-BLN/P(VDF-HFP) nanocomposite film reached 14.2 J/cm³ with the addition of 3 vol% BT-BLN nanofiller at 497 MV/m, which is much higher than that of pure P(VDF- HFP) (U_d ≈ 6.6 J/cm³ and E_b ≈ 391.3 MV/m). Encouragingly, the Young's modulus of BLN-3vol%/P(VDF-HFP) reached 2.6 GPa, which is approximately 2.65 times higher than that of pure P(VDF-HFP) (0.98 GPa). This work established a simple and effective strategy, for solution casting processable dielectrics with performance comparable to that of fillers prepared by the liquid phase method.