Development of Ba_(0.95)Sr_(0.05)(Fe_(0.5)Nb_(0.5))O_3/poly(vinylidene fluoride) nanocomposites for energy storage

摘要

To obtain high energy density with low dielectric loss, we synthesized polymer/ceramic composite by incorporating the giant dielectric constant material [Ba_(0.95)Sr_(0.05)(Fe_(0.5)Nb_(0.5))O_3] in a poly(vinylidene fluoride) (PVDF) polymer matrix. X-ray diffraction analysis confirmed the single phase monoclinic structure in all the composite samples. Microstructural analysis indicates that the Ba_(0.95)Sr_(0.05)(Fe_(0.5)Nb_(0.5))O_3 ceramics are evenly distributed in the PVDF matrix in all the composition. The high dielectric constant (～4045) with low dielectric loss (～0.06) was obtained for 10 wt% PVDF content in composite at room temperature. We found high energy density (3.02 J/cm~3) for 10 wt% PVDF content in composite at room temperature. These results may be exploited in the development of high energy density capacitors. A significant variation of dielectric constant with magnetic field was noticed, which was not reported previously.