Enhanced electromechanical performance of PSZT-PMS-PFW through morphotropic phase boundary design and defect engineering

It is desirable but challenging to explore piezoelectric ceramics with high mechanical quality factor Q(m) and large mechanical piezoelectric coefficient d(33) simultaneously because of the intrinsic restriction between d(33) and high Q(m). This work combines morphotropic phase boundary (MPB) with defect engineering to solve the above problem. It not only achieves low energy barriers between polar states near MPB but also introduces oxygen vacancy suppressing the movement of domain walls. Guided by theoretical design, we synthesize PbFe2/3W1/3O3 doped Pb0.95Sr0.05Zr0.52Ti0.48O3-PbMn1/3Sb2/3O3 ceramics. As a classical relaxor dopant, PbFe2/3W1/3O3 tends to change the local structure of Pb-based perovskite ferroelectrics and introduces multiply charged defect dipoles. Excellent comprehensive piezoelectric performance with a large d(33) of & SIM;390 pC N-1 and a high Q(m) value of & SIM;1000 is obtained in the Pb0.95Sr0.05Zr0.52Ti0.48O3-PbMn1/3Sb2/3O3-PbFe2/3W1/3O3 ternary system. Moreover, the d(33) value increases by over 60% while the Q(m) remains almost unchanged as compared to the properties of the undoped 0.9Pb(0.95)Sr(0.05)Zr(0.52)Ti(0.48)O(3)-0.1PbMn(1/3)Sb(2/3)O(3) ceramic. By Rietveld structural refinement of X-ray powder diffraction, piezoresponse force microscopy, and X-ray photoelectron spectroscopy, it is demonstrated that the excellent piezoelectric performance should be ascribed to the formation of nanoscaled inhomogeneous microstructures resulting from the morphotropic phase boundary and the unchanged Q(m) value should be attributed to the inhibition of the movement of domain walls resulting from defect dipoles. Our research provides a novel idea for developing piezoelectric ceramics with high d(33) and large Q(m) by combining MPB with defect engineering. It is expected to benefit a wide range of high-power piezoelectric ceramics.