Probing ferroelectric domain-polarization coupling mechanisms in polycrystalline PZT ceramics

The quenching process is investigated to modulate domain structures behaviors in three ceramic compositions: lead zirconate titanate with a 75/25 zirconium titanium ratio (75/25PZT), Mn-doped (Mn-75/25PZT) and Nb-doped (Nb-75/25PZT). Piezoresponse force microscopy (PFM) demonstrates a transformation of domain structures from micron to nanoscale, accompanied by increased domain walls (DWs) density. In-situ Raman spectroscopy detects a softening of the E (TO1) vibration mode after quenching, indicating lower DWs energy density and higher internal stress. Furthermore, both 75/25PZT and Mn-75/25PZT demonstrate the release of pinched hysteresis loops, coupled with substantial enhancements in piezoelectric coefficients of 36 % and 37 %, respectively. Additionally, both reversible and irreversible dielectric responses are augmented through quenching. This investigation provides detailed insights into the evolution of domains during the quenching process in these ceramic systems.