Isothermal phase transition across phase boundary in (Pb_0.95Ba_0.05)ZrO₃ceramics

Paraelectric-ferroelectric-antiferroelectric (PE-FE-AFE) phase transitions induced by external stimulus (temperature, electric field, and hydrostatic pressure) usually produce exotic performances in functional ceramics. This Letter reports an isothermal phase transition in (Pb0.95Ba0.05)ZrO3 ceramics in the proximity of separated PE-FE and FE-AFE phase boundaries as extended waiting time. Through an isothermal process, PE (Pm 3 ¯m)-to-FE (R3cH) and FE-to-AFE (Pbam) phase transformations occur within several minutes (with different transition degrees). This is in contrast to the wide recognition of ultrafast and time-independent ferroelectric transitions. In situ Raman spectra analysis unveils the sluggish growth of FE and AFE phases out of the corresponding parent matrix. Finally, the Landau theory analysis is proposed to explain the isothermal phase transition among PE-FE-AFE phases. This work will refresh the wisdom of phase transitions in functional ceramics.