Flexible Self-Poled P(VDF-TrFE)/SnO2 Composite Piezoelectric Film for Energy Harvesting and Wearable Sensors

Self-polarized devices have been increasing more interest in recent years in wearable electronics owing to their simple fabrication method and self-powering nature. In this work, we have demonstrated the self-polarized P(VDF-TrFE)/ SnO2 composite thin films on flexible substrate and investigated the effect of blending 5 wt% SnO2 in P(VDF-TrFE) to improve the crystallinity as well as piezoelectric performance without any additional polling. Compared to pure P(VDF-TrFE) film, the P(VDF-TrFE)/ SnO2 composite film with 5 wt.% exhibited the highest piezoelectric performance with an open circuit output voltage of 8.9 V, with power density of 2.3 mW/cm3 under a compressive force of 6 N applied at frequency of 1 Hz, which is 11 times higher than pure P(VDF-TrFE) film. The resulting composite film can be employed as a piezoelectric sensor for detecting low frequency human motions and has the potential application in smart wearable devices.