Enhanced Dielectric and Ferroelectric Properties in Flexible Bi ₂ FeNiO ₆ Films

Herein, enhanced dielectric and ferroelectric behavior of double perovskite Bi 2 FeNiO 6 (BFNO) embedded in polyvinylidene fluoride (PVDF) matrix using the solution‐casting method is reported. The presence of A 1 g , E g , and F 2 g modes in the Raman spectra of the BFNO‐PVDF flexible film has confirmed the retention of the Fm‐3m space group of BFNO even after the composite formation. Its microstructural studies with energy dispersive spectroscopy have revealed the uniform dispersion of BFNO nanoparticles within the PVDF network. The room temperature dielectric constant and loss tangent are found to be 652 and 2.5, respectively, at 1 kHz. The frequency and field‐dependent ferroelectric measurements demonstrate a significant increment in P r and E c values as compared to those of the pristine BFNO. This enhanced ferroelectric behavior in the BFNO‐PVDF composite is attributed to the insulating nature of PVDF, which effectively suppresses leakage current and facilitates efficient domain switching by electrically isolating the BFNO grains. Magnetic characterization reveals soft ferromagnetic behavior with M s = 4.49 emu g −1 and H c = 0.19 kOe. Electron spin resonance analysis yields Lande g ‐factor of 2.4, suggesting strong spin‐orbit coupling and local structural distortion. The coexistence of ferroelectric and magnetic ordering in the BFNO‐PVDF composite highlights its potential for multifunctional applications in flexible magnetoelectric and spintronic devices.