High-resolution synchrotron XRD study of Zr-rich compositions of Pb(Zr_xTi_1-x)O_3 (0.525\leq x \leq 0.60): evidence for the absence of the rhombohedral phase

TL;DR

This study uses high-resolution synchrotron XRD to analyze Zr-rich Pb(Zr_xTi_1-x)O_3 compositions, revealing a monoclinic structure and the absence of the rhombohedral phase near the morphotropic phase boundary.

Contribution

It provides detailed structural analysis showing the monoclinic phase in Zr-rich PZT and challenges the assumption of rhombohedral phase presence in this composition range.

Findings

Monoclinic structure in Zr-rich PZT confirmed

Absence of rhombohedral phase near MPB

Structural distortion varies with composition

Abstract

Results of Rietveld analysis of the synchrotron XRD data on Pb(Zr_xTi_1-x)O_3 (PZT) for 0.525\leqx\leq0.60 are presented to show the absence of rhombohedral phase on the Zr-rich side of the morphotropic phase boundary (MPB). Our results reveal that the structure of PZT is monoclinic in the Cm space group for 0.525\leq x\leq 0.60. The nature of the monoclinic distortion changes from pseudo-tetragonal for 0.525\leqx\leq0.54 to pseudo-rhombohedral for x>0.54.