LAUSR

Abstract A series of BiFe0.98Mn0.02O3/Sr2Bi4Ti5O18(BFMO/SBT) double-layer composite films with different transition thickness were prepared via a sol-gel method, and the effect of the thickness of SBT as transition layer on the performance of the BFMO/SBT double-layer composite films was researched. According to the XRD and SEM analyses, the perovskite structure was formed in all film samples. The BS40 sample had good crystallization, good density, uniform and small grain size. It could be seen from the XPS results that the Fe2+ and ( V O 2 − ) • • concentrations were the lowest in this sample. In addition, the 40 nm transition layer contributed to enhancing the piezoelectric (d33∼121 pm/V) and ferroelectric properties (2Pr∼99 μC/cm2@1250 kV/cm, 2Ec∼846 kV/cm) and reducing the leakage current density (J∼5.21 × 10−5A/cm2@350 kV/cm) of the sample due to the coupling effect between SBT and BFMO layers and the action of stress. The magnetic properties of the samples decreased derived from the grain size effect after the SBT transition layer was introduced. Since the degree of aging depended on the rearrangement of the defect dipoles affected by the oxygen vacancy concentration, the samples with the transition layer were weak in the aging degree.