Properties of piezoelectric ceramic with textured structure for energy harvesting

Piezoelectric ceramics with microstructure texturing were fabricated and evaluated to investigate its feasibility to use in piezoelectric energy harvesting in response to external mechanical impact. Textured 0.945(Bi0.5Na0.5)TiO3–0.55BaTiO3 (BNTBT) ceramics were prepared by tape casting of slurries containing a template SrTiO3 (STO). The orientation factor of more than 60% was obtained successfully when a plate-like SrTiO3 was used as the templates using a tape casting process. The sections perpendicular to the sheet plane of BNTBT ceramics exhibited preferentially [0 0 1] oriented orientation. Under low stress-loading, the voltage and power value of STO-added BNTBT were slightly higher than those of the specimen without STO. Meanwhile, the STO-added specimens showed excellent power over the STO-free specimen when a high stress was applied. When low stress was applied to the specimens, the reduction of piezoelectric characteristics by the addition of STO in BNTBT may be prominent in that the mixture of ferroelectric BNTBT and the non-ferroelectric STO has less ferroelectric features compared with the pure ferroelectric BNTBT. In contrast, under high field and stress signal the textured microstructure along to 〈1 0 0〉 is a feature of the improved piezoelectric behavior.