Superior high-temperature capacitive properties in high-entropy ferroelectric fillers/polymer nanocomposites

Dielectric polymer capacitors are key components of modern electronic and electrical power systems due to their high power density and quick charge-discharge rate. However, their U_e and η severely deteriorate at elevated temperature. This hinders their application in hybrid electric vehicles, underground oil and gas explorations, etc., which necessitate the next­generation capacitors with operating temperatures of ≥150 °C.

In this work, the authors report a great breakthrough in the fabrication of high-entropy ferroelectric fillers/polymer nanocomposites with outstanding high-temperature energy storage properties superior to state-of-the-art dielectric polymer composites. (Bi_0.2Na_0.2Ba_0.2Sr_0.2Ca_0.2)TiO₃ (BNBSCT) high-entropy ferroelectric fillers featuring inhomogeneous polarization configuration are designed. Taking advantage of this strategy, excitingly, the high-entropy ferroelectric fillers/polymer nanocomposites exhibit an ultra-high U_dis of 8.7 J cm^-3 (h=90.4%) at 150 ^oC and 5.9 J cm^-3 (h=90.6%) at 200 ^oC, which exceed most of the reported polymer nanocomposites with the h of over 90%.

This study overrides the empirical rule in high-temperature dielectric nanocomposites that the U_e and h can only be enhanced at the expense of each other.

The work entitled “Inhomogeneous Polarization Configuration of High-Entropy Fillers Boosting High-Temperature Capacitive Performances of Polymer Nanocomposites” was published in Advanced Powder Materials (available online on 27 June 2026).