Synergistic Optimization of Energy Storage Density of PYN‐Based Antiferroelectric Ceramics by Composition Design and Microstructure Engineering

PbYb0.5Nb0.5O3 (PYN)‐based ceramics, featured by their ultra‐high phase‐switching field and low sintering temperature (950 °C), are of great potential in exploiting dielectric ceramics with high energy storage density and low preparation cost. However, due to insufficient breakdown strength (BDS), their complete polarization‐electric field (P‐E) loops are difficult to be obtained. Here, to fully reveal their potential in energy storage, synergistic optimization strategy of composition design with Ba2+ substitution and microstructure engineering via hot‐pressing (HP) are adopted in this work. With 2 mol% Ba2+ doping, a recoverable energy storage density (Wrec) of 10.10 J cm−3 and a discharge energy density (Wdis) of 8.51 J cm−3 can be obtained, supporting the superior current density (CD) of 1391.97 A cm−2 and the outstanding power density (PD) of 417.59 MW cm−2. In situ characterization methods are utilized here to reveal the unique movement of the B‐site ions of PYN‐based ceramics under electric field, which is the key factor of the ultra‐high phase‐switching field. It is also confirmed that microstructure engineering can refine the grain of ceramics and improve BDS. This work strongly demonstrates the potential of PYN‐based ceramics in energy storage field and plays a guiding role in the follow‐up research.