Molecular-Scale Design of Piezoelectric Core-Shell Nanofibers for Wearable Electronic Devices Application

Wearable electronics as a viable mean to realize human-machine interaction have been developed and evolved over the centuries. Polymer-based piezoelectric materials, which can conformably covert human motions to electrical signals, exhibit excellent potential in the application of wearable electronics. However, the discovery and design of functional composites with high piezoelectricity and long-term stability is a significant challenge. Limited study has focused on theoretical modeling approaches to design high-performance polymer-based piezoelectric materials. Herein, we adopt the molecular dynamic approach to design a core-shell structure polyvinylidene fluoride (PVDF) based composite with enhanced crystallinity and electroactivity. Based on the results from the molecular dynamic simulation, the strong intermolecular interaction among the hydrogen bonding is an effective strategy to enhance the crystalline phase of the PVDF. In addition, we synthesized the nano-fibrous composites using the sol-gel method with a piezoelectric shell structure and conductive core structure. The optimized core-shell structure and enhanced crystallinity were confirmed by the experimental characterization results. The as-fabricated flexible piezoelectric devices exhibit significantly enhanced piezoelectricity with a 4 times increase in signal intensity. This unique core-shell structure of piezoelectric nanofibers opens up broader applications such as the Internet of Things and the human-machine interface. Moreover, this work could provoke a new approach for accelerating the design and discovery of functional materials for wearable electronics by using molecular dynamics simulation.