Enhanced multifunctional performance in NT doped BNBT/PVDF flexible ceramics composites

High-performance lead-free BNBT/PVDF composite ceramics with different NT concentrations (BNP-0, BNP-1, BNP-2) were successfully synthesized and analyzed. X-ray diffraction examination verified the presence of both rhombohedral and tetragonal phases, suggesting a morphotropic phase boundary, alongside the electroactive β-phase of PVDF, hence assuring high electrical response. With the increasing NT concentration leads to improved polarization, with BNP-1 achieving the highest maximum polarization (P_m = 2.14 μC/cm²) at 50 kV/cm. which further increases to 4.94 μC/cm² at high electric field. Stable permittivity throughout a wide frequency range, demand with the highest values (ε_r = 35) reported for BNP-1, and negligible dielectric losses (tan δ =0.016) at low to intermediate frequencies. Electrochemical study demonstrated improved pseudocapacitive behavior (∼1382 C/g) in the ideally doped BNP-1 composite, as well as increased charge storage capacity. Overall, the results show that carefully adjusting the NT content can improve ferroelectric, charge-storage, and dielectric performance all at once. This makes these composites excellent candidates for eco-friendly energy harvesting and flexible electronic applications.