Effect of 40 MeV Li3+ ion irradiation on dielectric and ferroelectric properties of (1-x)PVDF/(x)BaTiO3 nanocomposites

摘要

The (1-x)PVDF/(x)BaTiO3 nanocomposite films were prepared by solution mixing method. The dielectric constant (epsilon') was increased by the BaTiO3 incorporation in PVDF matrix. Further, the pristine PVDF and (1-x)PVDF/(x)BaTiO3 nanocomposite films were irradiated with 40 MeV Li-3(+) ion beam from 15 UD Pelletron at Inter University Accelerator Center, New Delhi. The uniform irradiation effect is observed as the projected range values (calculated from SRIM-2008) are much larger than the sample thickness (similar to 0.06 mm). After irradiation, recrystallization and alpha ->beta phase transition were observed in PVDF. However, almost complete amorphization was observed in BaTiO3 filler in (1-x)PVDF/(x)BaTiO3 nanocomposite samples. After 40 MeV Li-3(+) ion irradiation, the dielectric constant (epsilon') and remanence polarization decrease for all the samples while, the coercive field increases. This is interesting to note that BaTiO3 phase is amorphized through 40 MeV Li-3(+) ion irradiation, which also causes to decrease the dielectric constant along with cross-linking effect in (1-x)PVDF/(x)BaTiO3 nanocomposite films.