Porous flexible molecular-based piezoelectric composite achieves milliwatt output power density

Molecular ferroelectrics have made breakthrough progress in intrinsic piezoelectric response that can be on par with advanced inorganic piezoelectric ceramics. However, their successful applications in high-density energy harvesting and self-powered flexible devices have been great challenge, owing to the low elastic moduli, intrinsically brittle, and fracture proneness of such material systems under mechanical loading. Here, we have developed a flexible porous composite piezoelectric material by using soft thermoplastic polyurethane (TPU) and molecular ferroelectric materials. Benefiting from the porous structure of TPU, the flexible piezoelectric composites enable effectively large doping ratio (50%) of [Me