Biomimetic Porifera Skeletal Structure of Lead-Free Piezocomposite Energy Harvesters.

The elastic composite-based piezoelectric energy-harvesting technology is highly desired to enable a wide range of device applications, including self-powered wearable electronics, robotic skins, and biomedical devices. Recently developed piezoelectric composites are based on inorganic piezoelectric fillers and polymeric soft matrix to take advantages of both components. However, there are still limitations such as weak stress transfer to piezoelectric elements and poor dispersion of fillers in matrix. In this report, a highly enhanced piezocomposite energy harvester (PCEH) is developed using a three-dimensional electroceramic skeleton by mimicking and reproducing the sea porifera architecture. This new mechanically reinforced PCEH is demonstrated to resolve the problems of previous reported conventional piezocomposites and in turn induces stronger piezoelectric energy-harvesting responses. The generated voltage, current density, and instantaneous power density of the biomimetic PCEH device reach up to ∼16 times higher power output than that of conventional randomly dispersed particle-based PCEH. This work broadens further developments of the high-output elastic piezocomposite energy harvesting and sensor application with biomimetic architecture.