Thermally stimulated depolarization current of BaTiO/sub 3//PVDF(70)-TrFE(30) 0-3 ferroelectric composites

摘要

0-3 ferroelectric composites of barium titanate (BT) and vinylidene fluoride-trifluoroethylene copolymer P[VDF(70)-TrFE(30)] with different volume fraction of BT were prepared by solution blending followed by compression-molding. The thermally stimulated depolarization current (TSDC) of the composites has been measured. Three detrapping charge and two phase transition peaks (one for copolymer and another for ceramic) are observed in TSDC spectra above room temperature. For the composite sample in which only the ceramic phase is polarized, the detrapping charge peaks disappeared, which indicates that the TSDC originates from the copolymer phase. According to the analysis of phase transition, the structural origin of TSDC peaks is proposed. The detrapping charge density increases as increasing BT content, which shows that ceramic inclusions enhance the ability of charge storage in the composites.