Interfacial phase engineering and electrical response in BLFO/BPFO–BZT/PVDF lead-free ceramic–polymer composites

Lead-free ceramic–polymer composites represent a promising route toward flexible electromechanical devices. In this study, BLFO/BPFO–BaZr _0.2 Ti _0.8 O ₃ ceramics were synthesized and incorporated into a poly (vinylidene fluoride) (PVDF) matrix to fabricate multifunctional composites. Structural analysis revealed the coexistence of rhombohedral and orthorhombic phases in the ceramic component, consistent with a morphotropic phase boundary (MPB) region. Raman spectroscopy confirmed lattice distortion associated with A-site substitution, while FTIR analysis demonstrated enhanced formation of the electroactive (β+γ)-phase of PVDF. The composite containing 75 wt.% ceramic exhibited the electrical output (∼230 mV), highlighting the dominant ferroelectric contribution of the ceramic phase within the polymer matrix. These results establish a good structure–interphase–property relationship and demonstrate that phase coexistence engineering combined with polymer-phase modulation is an effective strategy for designing lead-free ceramic–polymer composites.