Structure and electrical properties in CuO-modified BCZT lead-free piezoelectric ceramics

Ba0.85Ca0.15Zr0.1Ti0.9O3-x wt% CuO (BCZT-xCu) lead-free piezoelectric ceramics were designed and synthesized using a traditional solid-state reaction method to improve both the relaxor behavior and the electrical properties of BCZT lead-free piezoelectric ceramics. The Cu2+ diffuses into the BCZT lattice and forms ABO(3) perovskite solid solution. Additionally, X-ray diffraction patterns and Raman spectra reveal that the introduction of CuO causes phase transition from the O-T phase coexistence to the O phase in BCZT-xCu. SEM displays that BCZT-xCu has a well microstructure at CuO doping amount between 0.5 wt% and 1 wt%. With the increasing CuO content, the orthorhombic-tetragonal (TO-T) phase transition shifted towards higher temperature, while Curie temperature (T-c) shifted towards lower temperature. Moreover, the dielectric diffusivity gamma increases from 1.63 to 1.92 as x increases. Results indicate that optimal electrical properties, namely d(33) = 315 pC/N, k(p) = 34%, epsilon(r) = 3213, tan delta = 2.71%, P-r = 7.45 mu C/cm(2) and E-c = 2.75 kV/cm are achieved in the 1 wt% CuO added ceramic sintered at 1250 & DEG;C for 2 h.

Automated summary

BCZT-xCu lead-free piezoelectric ceramics were synthesized using a solid-state reaction method with CuO doping, which formed ABO(3) perovskite solid solution. X-ray diffraction and Raman spectra analysis revealed a phase transition caused by the introduction of CuO. Optimal electrical properties were achieved in the ceramic sintered at 1250℃ with 1 wt% CuO.