Electrocaloric Effect of Structural Configurated Ferroelectric Polymer Nanocomposites for Solid-State Refrigeration.

To successfully complete the design of high-performance electrocaloric devices for advanced flexible cooling systems, it is necessary to comprehensively consider the optimization of composite materials, structural design of nanocomposites, and device integration. The cooling power density and energy storage density of various structural configurated poly(vinylidene fluoride) (PVDF)-based polymer nanocomposites are investigated using a phase-field model through the general formulation of a partial differential equation of COMSOL Multiphysics and finite element analysis through Maxwell's equation of conservation of charge. It is revealed that ferroelectric polymer nanocomposites composed of boron nitrate fibers (BN) + BCZT@BaTiO + PVDF possess the optimal result regarding their cooling power as well as the energy storage density. The cooling power density of the core-shell-structured BN + BCZT@BaTiO + PVDF nanocomposites is evaluated as a function of the volume content, frequency, and electric field, where a remarkable cooling power density of 162.2 W/cm is achieved at 4 Hz with energy storage density of 33.4 J/cm under a 500 MV/m field. Therefore, by performing the systematic study of the electrocaloric effect in structural configurated ferroelectric polymer nanocomposites for solid-state refrigeration, this opens an avenue for developing remarkably improved power density with reduced weight in aerospace energy storage technology.