Phase-formation, microstructure, and piezoelectric/dielectric properties of BiYO3-doped Pb(Zr0.53Ti0.47)O3 for piezoelectric energy harvesting devices

Abstract

Abstract This paper proposes a method for the composition and synthesis of lead zirconate titanate (PZT) piezoelectric ceramic for use in energy harvesting systems. The proposed material consists of (1− x )Pb(Zr 0.53 Ti 0.47 )O 3 – x BiYO 3 [PZT–BY( x )] ( x =0, 0.01, 0.02, 0.03, 0.04, and 0.05 mol) ceramics near the morphotropic phase boundary (MPB) region, prepared by a solid-state mixed-oxide method. The optimum sintering temperature was found to be 1160 °C, which produced high relative density for all specimens (96% of the theoretical density). Second phases were found to precipitate in the composition containing x ≥0.01 mol of BY. It is shown that the addition of BY inhibits grain growth, and exhibits a denser and finer microstructure than those in the un-doped state. Fracture surface observation revealed predominant intergranular fracture for x =0 and x =0.01, while a mixed mode of transgranular and intergranular fracture appeared for x ≥0.02. The optimal doping level was found to be x =0.01, for which a dielectric constant ( K 33 T ) of 750, a Curie temperature ( T C ) of 373 °C, a remnant polarization ( P r ) of 50 µC/cm 2 , a piezoelectric constant ( d 33 ) of 350 p C/N, and an electro-mechanical coupling factor ( k p ) of 65% were obtained. In addition, the piezoelectric voltage constant ( g 33 ), and transduction coefficient ( d 33 × g 33 ) of PZT–BY( x ) ceramics have been calculated. The ceramic PZT–BY(0.01) shows a considerably lower K 33 T value, but higher d 33 and k p . Therefore, the maximum transduction coefficient ( d 33 × g 33 ) of 18,549×10 −15 m 2 /N was obtained for PZT–BY(0.01). The large ( d 33 × g 33 ) indicates that the PZT–BY(0.01) ceramic is a good candidate material for energy harvesting devices.