Piezoelectric Polyacrylonitrile Nanofiber Film-Based Dual-Function Self-Powered Flexible Sensor

within the range of 0.15-25 N. The sensor had a long stability over 60 000 cycles at both sensing modes. The inclusion of barium titanate nanoparticles (BTO NPs) into the nanofiber film had an over 2.4 times enhancement of sensitivity for pressure sensing because of the synergy of piezoelectric and triboelectric effects. On the basis of multifunction and modularity, a series of potential applications of the sensor were demonstrated, including sensing human's swallowing, walking gaits, finger flexure, and finger-tapping. The self-powered flexible dual-mode sensor has great application potential in human-computer interactive and smart wearable sensing systems.