Microstructure and Impedance Analysis of CaBi4Ti4O15 Piezoceramics with (LiCe)-Modifications

(Li,Ce) doped CaBi4Ti4O15 (CBT) ceramics were prepared using the conventional solid state method. The crystal structure and microstructure of CBT-based ceramics were determined by the X-ray diffraction and scanning electron microscopy. It was found that the (Li, Ce) ions diffused into the A site of pseudo-perovskite structure and formed single Aurivillius type structure. The Curie-temperature (T-C) of CBT ceramics decreased whereas the piezoelectric coefficient (d(33)) was improved with the increasing of (Li,Ce) dopants. Furthermore, the impedance spectrum techniques were invoked to understand the electrical properties for pure or modified-CBT compounds at high temperature region and the underlying physical mechanism were also discussed.