Influence of CeO2 doping amount on property of BCTZ lead-free piezoelectric ceramics sintered at low temperature

Ba0.85Ca0.15Ti0.9Zr0.1O3 (BCTZ) lead-free piezoelectric ceramics co-doped with CeO2 (x=0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%) and Li2CO3 (0.6 wt.%) were prepared by conventional solid-state reaction method. Influence of CeO2 doping amount on the piezoelectric properties, dielectric properties, phase composition and microstructure of prepared BCTZ lead-free piezoelectric ceramics doped with Li2CO3 were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) and other analytical methods. The results showed that the sintered temperature of BCTZ lead-free piezoelectric ceramics doped with CeO2 decreased greatly when Li2CO3 doping amount was 0.6 wt.%; a pure perovskite structure of BCTZ lead-free piezoelectric ceramics co-doped with Li2CO3 and CeO2 and sintered at 1050 °C could also be obtained. The piezoelectric constant (d33), the relative permittivity (ɛr) and the planar electromechanical coupling factor (kp) of BCTZ ceramics doped with Li2CO3 increased firstly and then decreased, the dielectric loss (tanδ) decreased firstly and then increased and decreased at last when CeO2 doping amount increased. The influence of CeO2 doping on the properties of BCTZ lead-free piezoelectric ceramics doped with Li2CO3 were caused by “soft effect” and “hard effect” piezoelectric additive and causing lattice distortion. When CeO2 doping amount (x) was 0.2 wt.%, the BCTZ ceramics doped with Li2CO3 (0.6 wt.%) and sintered at 1050 °C possessed the best piezoelectric property and dielectric property with d33 of 436 pC/N, kp of 48.3%, ɛr of 3650, tanδ of 1.5%.

Graphical AbstractXRD patterns of BCTZ ceramics co-doped with Li2CO3 (0.6 wt.%) and CeO2 (x) in 2θ=20°–80°Figure optionsDownload as PowerPoint slide