Lead-Free Piezoelectric Composite Based on a Metamaterial for Electromechanical Energy Conversion

Additive manufacturing of arbitrary shapes and unique architecture provides remarkable flexibility and simplicity for the preparation of highly complex conformal electronics. This drives up demand for electronic materials with excellent process ability and functionality from one-step molding of microminiature to large-scale devices. Herein, a novel method is introduced for fabricating high-performance barium titanate (BaTiO3)-polydimethylsiloxane composites based on three-dimensional (3D)-printing-ordered structure of a metamaterial skeleton. When subjected to external mechanical stress, the metamaterial structure facilitates effective stress transfer, resulting in a significantly improved voltage output. In comparison to traditional low-dimensional ceramic polymer composites, metamaterial-structured BaTiO3 composites exhibit excellent electromechanical energy conversion properties, thereby enabling tactile imitation applications and mechanical energy harvesting. This study proposes a novel strategy for biological signal identification and implantable self-powered electronic applications.