In-situ engineered PVDF/α-Fe ₂ O ₃ nanocomposite films with enhanced dielectric and magnetic properties

This study addresses the growing demand for flexible multifunctional materials by developing self-supporting nanocomposite thin films of polyvinylidene fluoride (PVDF) reinforced with in-situ co-precipitated α-Fe 2 O 3 nanoparticles (0, 5, 10 and 15wt.%). The objective is to investigate the influence of filler concentration on structural evolution and functional properties. XRD results reveal enhanced structural organization, with crystallinity increasing from 41.19% to 54.87%, while SEM analysis shows a reduction in porosity from 14.80% to 9.04%. The β/α phase ratio increases significantly from 4.83 to 11.80, indicating effective stabilization of the electroactive β-phase due to nanoparticle incorporation. FTIR and Raman analyses further confirm phase transformation and molecular interactions. Dielectric studies demonstrate a systematic improvement, with the dielectric constant at 10 2 Hz increasing from ∼9 (pristine PVDF) to ∼23 for 15 wt.% composites, attributed to Maxwell–Wagner interfacial polarization. This enhancement is accompanied by reduced dielectric loss, suggesting restricted polymer chain mobility and lower energy dissipation. AC conductivity also increases, reaching ∼1.2 × 10 -3 S/m at higher frequencies. Magnetic measurements reveal soft ferromagnetic behavior with magnetization proportional to filler content. These nanocomposites exhibit strong potential for flexible electronics and electromagnetic interference shielding applications.