Lead-free ceramics （Ba0.85Ca0.15）（Zr0.1Ti0.9）O3-x wt,%Cr2O3 （BCZT-xCr） were prepared via the conventional solid-state reaction method. The microstructure and electrical properties of BCZT-xCr samples were system...Lead-free ceramics （Ba0.85Ca0.15）（Zr0.1Ti0.9）O3-x wt,%Cr2O3 （BCZT-xCr） were prepared via the conventional solid-state reaction method. The microstructure and electrical properties of BCZT-xCr samples were systematically studied. XRD and Raman results showed that all samples possessed a single phased perovskite structure and were close to the morphotropic phase boundary （MPB）. With the increase of the Cr content, the rhombohedral-tetragonal phase transition temperature （TR-T） increases slightly, and the Curie temperature （Tc） shifts towards the low temperature side. XPS analysis reveals that Cr3. and Cr5＊ ions co-existed in Cr-doped BCZT ceramics, indicating the different impact on the electrical properties from Cr ions as ＂acceptor＂ or ＂donor＂. For the x = 0.1 sample, relative high piezoelectric constants d33 （-316 pC/N） as well as high Qm （-554） and low tan6 （-0.8%） were obtained. In addition, the AC conductivity was also investigated. Hopping charge was considered as the main conduction mechanism at low temperature. As the temperature increases, small polarons and oxygen vacancies conduction played important roles.展开更多
文摘Lead-free ceramics （Ba0.85Ca0.15）（Zr0.1Ti0.9）O3-x wt,%Cr2O3 （BCZT-xCr） were prepared via the conventional solid-state reaction method. The microstructure and electrical properties of BCZT-xCr samples were systematically studied. XRD and Raman results showed that all samples possessed a single phased perovskite structure and were close to the morphotropic phase boundary （MPB）. With the increase of the Cr content, the rhombohedral-tetragonal phase transition temperature （TR-T） increases slightly, and the Curie temperature （Tc） shifts towards the low temperature side. XPS analysis reveals that Cr3. and Cr5＊ ions co-existed in Cr-doped BCZT ceramics, indicating the different impact on the electrical properties from Cr ions as ＂acceptor＂ or ＂donor＂. For the x = 0.1 sample, relative high piezoelectric constants d33 （-316 pC/N） as well as high Qm （-554） and low tan6 （-0.8%） were obtained. In addition, the AC conductivity was also investigated. Hopping charge was considered as the main conduction mechanism at low temperature. As the temperature increases, small polarons and oxygen vacancies conduction played important roles.
