Enhancement effect of two-tiered heterostructure in piezoelectric filler-dispersed polymer composites

•The effect of 2-tiered heterostructure was demonstrated by simulations and experiments.•The relation between the piezoelectric (PE) constant and phase connectivity was elucidated.•The connectivity of the PE phases in the applied electric field can effectively increase the PE constant.•PE constant can be improved by controlling the filler content of the phases in 2-tiered heterostructures.•A 2-tiered heterostructure was fabricated and demonstrated PE improvement of approximately 480 %. The effect of two-tiered heterostructure was verified by computational simulations and prototype experiments as a new approach for improving the performance of piezoelectric (PE) filler-dispersed polymer materials. Multiscale finite element analysis (FEA) based on asymptotic homogenization theory was applied to systematically investigate the fundamental properties of 0–3 composites in the first level and the relationship between macroscopic piezoelectricity and connectivity of the constituent phases in the second level. Simulations indicated that macroscopic piezoelectricity can be improved by controlling the PE filler content of the constituent phases in the two-tiered heterostructure, and that the connectivity of the PE phases in the direction of the applied electric field can effectively enhancing piezoelectricity. Furthermore, the two-tiered heterostructure discovered by multiscale FEA was fabricated by the melt-casting, demonstrating a piezoelectricity improvement of approximately 480 %. [Display omitted]