The pursuit of ferroelectric materials that combine a high piezoelectric response with robust thermal stability remains a paramount challenge. We introduce a strategy that integrates morphotropic phase boundary (MPB) engineering with high-entropy (HE) design in a novel quinary Pb(Yb1/2Nb1/2)O3-Pb(Zn1/3Nb2/3)O3-Pb(Fe1/2Nb1/2)O3-PbZrO3-PbTiO3 (PYN-PZN-PFN-PZ-PT) perovskite ceramic. Compared to a medium-entropy counterpart, the high-entropy composition yields a superior piezoelectric coefficient of 580 pC/N and exceptional thermal stability, with performance retained up to 285 °C. This enhancement arises from two synergistic effects of the HE design: a stabilized, flattened free-energy landscape that promotes a favorable nanoscale domain structure and improves depolarization behavior, together with higher electrical resistivity (1012 Ω·cm at 250 °C) arising from HE-driven grain refinement and suppressed charge transport. This work demonstrates that HE design serves as an effective strategy to mitigate the traditional trade-off between piezoelectric response and depolarization temperature in Pb-based relaxor ferroelectrics. The authors integrate morphotropic phase boundary engineering with high-entropy design in a quinary perovskite ceramic, which yields a piezoelectric coefficient of 580 pC/N and exceptional thermal stability, with performance retained up to 285 °C.
Karim et al. (Sat,) studied this question.