Antimony Oxide-Doped 0.99Pb(Zr0.53Ti0.47)O3–0.01Bi(Y1−xSbx)O3 Piezoelectric Ceramics for Energy-Harvesting Applications

The effects of doping antimony oxides (Sb2O3/Sb2O5) on the ferroelectric/piezoelectric and energy-harvesting properties of 0.99Pb(Zr0.53Ti0.47)O3–0.01BiYO3 (PZT–BY) have been studied. The feasibility of doping Sb2O3 and Sb2O5 into the PZT–BY ceramics has also been compared by considering factors such as sintering condition, grain size, density, and electrical properties etc. This work discusses a detailed experimental observation using Sb2O3, because Sb2O5 is relatively expensive and does not follow the stoichiometric reaction mechanism when doped in PZT–BY. The Sb2O3-doped specimens were well sintered by oxygen-rich sintering and reached a maximum density of 99.1% of the theoretical value. X-ray diffraction (XRD) analysis showed a complete solid solution for all the specimens. Scanning electron microscope (SEM) observation revealed that the addition of Sb2O3 inhibits grain growth, and exhibits a denser and finer microstructure. The 0.1 moles of Sb2O3-doped ceramic shows a sharp decrease in the dielectric constant (ε33T = 690), while the piezoelectric charge constant (d33) and electromechanical coupling factor (kp) maintained high values of 350 pC/N and 66.0% respectively. The relatively higher value of d33 and lower ε33T of the 0.99Pb(Zr0.53Ti0.47)O3–0.01Bi(Y0.9Sb0.1)O3 ceramic resulted in an optimum value of piezoelectric voltage constant (g33 = 57.4 × 10−3 Vm/N) and a high figure of merit (d33 × g33 = 20075 × 10−15 m2/N). These values are high compared to recently reported works. Therefore, Sb2O3-doped PZT–BY ceramic could be a promising candidate material for the future study of power-harvesting devices.