Trilayer structured ceramic/polymer nanocomposites with superior breakdown strength and discharged energy density

The excellent dielectric constant (ε_r) and breakdown strength (E_b) of dielectric nanocomposites are the necessary conditions for their excellent energy storage properties (ESPs) in microelectronics and power systems. In recent years, inorganic nanofillers and multilayer structure design have provided an efficient way to improve the ESPs of dielectric composites. Herein, we selected 0.8Bi_0.5(Na_0.82K_0.18)_0.5TiO₃-0.2Sr(Sc_0.5Nb_0.5)O₃ cecamic nanoparticles (BNKT-SSN NPs) with high ε_r and low loss as nanofillers, and prepare novel trilayer structured BNKT-SSN/P(VDF-HFP) nanocomposites to improve the ε_r and E_b. The investigated phenomena demonstrate that due to the contribution of BNKT-SSN NPs incorporation and interfacial polarization between neighboring layers, the ε_r and E_b of the trilayer structured BNKT-SSN/P(VDF-HFP) nanocomposites are enhanced while the dielectric loss (tanδ) and leakage current density are suppressed. It is worth noting that the E_b is measured up to 650 MV m⁻¹ when the intermediate layer fillers BNKT-SSN NPs of the trilayer structured nanocomposite is 0.75 vol%, and the discharged energy density (U_d) and energy efficiency (η) are 25.79 J cm⁻³ and 70.07 %, respectively. In this work, it's demonstrates that the incorporation of inorganic ceramic fillers and the trilayer structured design provide a feasible approach of improving the ESPs of dielectric nanocomposites.