Intrinsic piezoelectricity of PZT

TL;DR

This study measures the intrinsic piezoelectric properties of PZT near the MPB, revealing that the large piezoelectric response in ceramics is mainly due to extrinsic effects rather than intrinsic material properties.

Contribution

The paper introduces a novel growth method for c-axis oriented PZT near MPB on stainless steel, enabling direct measurement of intrinsic piezoelectric and ferroelectric properties.

Findings

Intrinsic d33 is approximately 46.4 pm/V, close to theoretical predictions.

Intrinsic properties are significantly smaller than ceramic responses, indicating extrinsic effects dominate.

Large piezoelectric response in ceramics is primarily driven by extrinsic effects.

Abstract

An unresolved issue in the commonly used Pb(Zr1-xTix)O3 (PZT) ceramics is understanding the intrinsic piezoelectric behaviors of its crystal around the morphotropic phase boundary (MPB). Here, we demonstrate a novel approach to grow c-axis oriented PZT around MPB on stainless steel SUS430, allowing us to estimate the intrinsic piezoelectric and ferroelectric properties of PZT along its polar axis. The piezoelectric coefficient d33 and spontaneous polarization Ps were found to be 46.4 +- 4.4 pm/V, 88.7+-4.6 uC/cm2, respectively, for x = 0.47 close to MPB. These values align well with the predicted values of d33 = 50 - 55 pC/N and Ps=79 uC/cm2 at room temperature from the first-principles-derived approach. The obtained d33 is 4 times smaller than that of its ceramics, indicating that the large piezoelectric response in the PZT ceramics around MPB is primarily driven by extrinsic effects rather than intrinsic ones. In the technical application of PZT films, achieving a substantial piezoelectric response requires careful consideration of these extrinsic effects.