Electrical Characteristics and Microstructures of Sm2O3-Doped Bi4Ti3O12 Ceramics

摘要

We investigate the electrical properties of Sm-doped Bi_(4-x)Sm_xTi_3O_(12) (BST) ceramics prepared by a conventional electroceramic technique. The x-ray diffraction analysis reveals the Bi-layered perovskite structure in all samples. The SEM micrographs show randomly oriented and plate-like morphology. For the samples with x = 0.4 and 1.0, the current–voltage characteristics exhibit negative differential resistance behaviour and the P–V hysteresis loops are characterized by large leakage current, whereas for the samples with x = 0.6 and 0.8, the current–voltage characteristics show simple ohmic behaviour and the P–V hysteresis loops are of the saturated and undistorted hysteresis. The remanent polarization and coercive field of the BST ceramic with x = 0.8 are above 32 μC/cm~2 and 70 kV/cm, respectively.