Synchronous Construction of Piezoelectric Elements and Nanoresistance Networks for Pressure Sensing Based on the Wheatstone Bridge Principle

Fabrication of flexible piezoelectric sensing nanomaterials is essential for the development of wearable and microscopic electronic devices. However, existing piezoelectric sensing materials usually rely on the secondary synthesis process to accomplish the preparation of conductive layer electrodes. Here, we report a one-step strategy for synchronous construction of piezoelectric elements and nanoresistance networks via fabricating flexible [polyacrylonitrile/BaTiO3]@[polyaniline/polyvinyl pyrrolidone] core–shell nanofibers (NFs, denoted [PAN/BTO]@[PANI/PVP]) by coaxial electrospinning. This is the first time to collect and output voltage signals generated by piezoelectric materials through nanoresistance networks based on the Wheatstone bridge principle. As a result, flexible [PAN/BTO]@[PANI/PVP] core–shell NFs as an integrated sensing system without layer electrodes can directly result in voltage signals under repeating press–release motions. The potential of a flexible core–shell [PAN/BTO]@[PANI/PVP] integrated nanofiber membrane (INFM) for pressure sensing is properly explored and evaluated. The integration of piezoelectric elements and nanoresistance networks enables the INFM to perceive pressures with high sensitivity (728 mV N–1) down to approximately 0.05 N and a quick response (26 ms). Overall, our study demonstrates a promising strategy to fabricate nanoscale, highly sensitive, and low-cost integrated sensing materials, which have potential applications in micro-/nanoscale sensors and wearable electronics.