Fig. 1: Strategy for enhanced energy storage performance of MLCCs with interlaminar strain engineering.

a Schematic of the MLCC (S4) with a periodical heterogeneous layer structure. b Comparative display of domain structures and polarization-electric field (P-E) loops of S1, S2 and S3 with high electric fields. With small domains, S1 and S3 show slim loops with near-zero hysteresis and remanent polarization, while their polarization is also low. In contrast, S2 with large FE domains possesses high polarization but obvious hysteresis. With strain engineering (S4), the in-plane tensile strain decreases the domain size of S2 to depress its hysteresis while the in-plane compressive strain increases the polarization of S1 and S3. With the domain engineering, S4 is expected to exhibit a high polarization like S2 and a near-zero hysteresis similar to S1 and S3 for achieving high energy storage density and efficiency, simultaneously (the P-E loop of S4).