Perovskite ferroelectric materials are at the heart of numerous electronic devices, such as imaging transducer, piezoelectric sensors, energy harvesting and energy storage capacitors, to name a few. Relaxor-PT ferroelectrics show superior dielectric/piezoelectric properties, outperforming conventional ferroelectric PZTs, which greatly benefit medical ultrasound imaging. The good properties of relaxor-PT based materials are inherently associated with their unique local structural heterogeneity: the existence of nanoscale heterogeneous regions that coexists with normal ferroelectric domains. The contribution of these local structures has been theoretically modelled to be the origin of the ultrahigh dielectric and piezoelectric activities of relaxor based perovskite ferroelectric crystals, accounting for 50-80% of their respective room temperature values. Based on the paradigm, recent developments have experimentally confirmed that modest changes in the polarizability of local structure, can be regarded as “seeds” to further enhance the dielectric properties of ABO3 perovskite solid solutions. The modified polycrystalline ceramics and crystals exhibit ultrahigh dielectric and piezoelectric properties, with high piezoelectric coefficient of 4000 pC/N. In addition, the energy storage performance of the local structure tuned perovskite ferroelectrics is also greatly enhanced, with energy density of >9 J/cc (20 microns ceramic layer) and energy efficiency of >90%. The relationship between local structure and macroscopic properties has been established, try to understand the impact of local structure on dielectric properties, to explore high performance ferroelectric materials for energy harvesting and energy storage applications.
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