  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.
