Collective dynamics of polar nanoregions enhance electrical properties via solid-solution-induced entropy increase in KBT relaxors

Relaxor ferroelectrics (RFEs) are renowned for excellent electromechanical properties, primarily driven by the presence of polar nanoregions (PNRs). Recent advances, including the entropy-increase strategy via various designs, enhance PNR density and disorder, but the underlying collective dynamics of PNRs and their impact on RFE electrical properties have received less attention. Here, we investigate the role of PNR collective dynamics by using K0.5Bi0.5TiO3 (KBT) as a model system and progressively enhancing PNR density through doping with Bi(Ni0.5Zr0.5)O3. It significantly improves KBT’s electrostrain and energy storge. We observe 10-1000 nm PNR mesostructures self-assembled from 2-4 nm PNRs, and via the Gray-Scott model, confirm their origin from Turing instability in PNR groups (a universal nanoscale self-organization mechanism for RFEs). And the jamming effects within these mesostructures play a key role in enhancing electrical properties. Our findings shed light on RFE’s structure-property relationships and provide guiding principles for designing other high-performance RFEs. Relaxor ferroelectrics (RFEs) are widely used for their excellent electrical properties rooted in polar nano regions (PNRs), yet how PNRs’ collective dynamic behavior impacts material performance is poorly understood. Taking KBT RFEs as a model, the authors identify unique PNR mesostructures, reveal their Turing instability origin, and clarify jamming effects as key to boosting their electrical properties.