Lead-free (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3–CeO2 ceramics with high piezoelectric coefficient obtained by low-temperature sintering

Abstract Lead-free (Ba 0.85 Ca 0.15 )(Ti 0.9 Zr 0.1 )O 3 – x %CeO 2 (BCZT– x Ce) piezoelectric ceramics have been prepared by the traditional ceramic process and the effects of CeO 2 addition on their phase structure and piezoelectric properties have been studied. The addition of CeO 2 significantly improves the sinterability of BCZT ceramics which results in a reduction of sintering temperature from 1540 °C to 1350 °C without sacrificing the high piezoelectric properties. X-ray diffraction data show that CeO 2 diffuses into the lattice of BCZT and a pure perovskite phase is formed. SEM images indicate that a small addition of CeO 2 greatly affects the microstructure. Main piezoelectric parameters are optimized at around x = 0.04 wt% with a high piezoelectric coefficient ( d 33 = 600 pC/N), a planar electromechanical coefficient ( k p = 51%), a high dielectric constant ( ɛ r = 4843) and a low dissipation factor (tan δ = 0.012) at 1 kHz, which indicates that the BCZT– x Ce ceramics are promising for lead-free practical applications.