Novel flexible piezoelectric-conductive Janus nanofibers integrated membrane with enhanced pressure sensing performance

摘要

Exploitation of soft piezoelectric sensing materials is fundamental to the research of energy-harvesting devices and wearable electronics. However, a big challenge of piezoelectric materials application in micro-scale sensing systems is to address the restrictions of electrode compatibility, miniaturization, multistep assembly, and high cost. Here, we propose a simple strategy to develop the coinstantaneous construction of piezoelectric materials and nanoresistance networks by fabricating electrospun piezoelectric-conductive (polyacrylonitrile)//(polyaniline/polyvinyl pyrrolidone) (denoted PAN//PANI/PVP) Janus nanofibers (NFs). This peculiar Janus structure can collect and output voltage by conductive paths based on the Wheatstone bridge principle. Moreover, owing to the nanoscale asymmetric geometry for efficient polarization and induced charges collection, the Janus NFs show superior piezoelectric properties. As a result, flexible (PAN)//(PANI/PVP) Janus nanofibers integrated membrane (JNFIM) dispensing with two flat electrodes can directly output a high voltage of 2 V under a tiny force of 1 N. Furthermore, the JNFIM enables to detect pressures with extra-high linear sensitivity (1.88 V N-1) and low detection limit (0.1 N). Thus, our work provides a simple route for the development of nanoscale, low-cost, and high-sensitivity integrated materials for pressure sensing, revealing promising applications in miniature robotics and wearable devices.