전기수력 불안정성을 이용한 PVDF-TrFE 박막의 표면 구조체 형성 및 유전 특성 향상 = Electrohydrodynamic Instability-Induced Surface Structuring of Poly(vinylidene fluoride-trifluoroethylene) Films for Enhanced Dielectric Performance

다국어 초록 (Multilingual Abstract)

Poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) is a promising ferroelectric polymer for flexible electronics and energy-harvesting devices, owing to its high piezoelectric coefficient and mechanical flexibility. Here, we report that electrohydrodynamic instability induces the formation of closely packed nanostructures on PVDF-TrFE thin film.
Intriguingly, the strong electric field used in the fabrication process drives the polymeric fluid of PVDF-TrFE upwards to form the surface structures, facilitating molecular dipole alignment and crystalline ordering. This effect contributes to improved crystal alignment, as confirmed by enhanced X-ray diffraction and Raman characteristic peaks. The nanostructured PVDF-TrFE films exhibit enhanced dielectric properties including permittivity, dielectric loss, and ferroelectric polarization.
Notably, P-E loop measurements showed a larger remnant polarization and higher saturation polarization in the nanostructured PVDF-TrFE films, indicating improved ferroelectric behavior. Our results suggest that the electrohydrodynamic instability provides a simple but effective route to simultaneously tailor the surface morphology, crystalline phase, and electrical performance of PVDF-TrFE films.