Optimized energy storage characteristics of PVDF/PVDF-TrFE all-organic composite dielectrics

Abstract

Polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) is a promising polymer for dielectric energy storage due to its high relative dielectric permittivity (ε_r), but its application is hindered by large dielectric loss and low chargedischarge efficiency. To address this, we introduced poly(vinylidene fluoride) (PVDF) to prepare PVDF/PVDF-TrFE all-organic composite films to obtain excellent energy storage characteristics. The introduction of PVDF effectively reduced the dielectric loss while maintaining a high dielectric constant. When the PVDF to PVDF-TrFE ratio is 1 : 2 (PP-3), the composite achieved optimal performance. It exhibited a high breakdown strength of 530 MV m⁻¹, an exceptional energy storage density of 11.11 J cm⁻³ (47.74% higher than pristine PVDF-TrFE), and a charge–discharge efficiency improved by 129.81%. This work demonstrates a simple and effective strategy for combining the advantages of both polymers, paving the way for the application of PVDF-TrFE in advanced dielectric capacitors.