Enhanced Piezoelectric Performance of Electrospun PVDF‐TrFE by Polydopamine‐Assisted Attachment of ZnO Nanowires for Impact Force Sensing

Abstract

AbstractIn this work, piezoelectric PVDF‐TrFE electrospun fibers (EFs) were fabricated using a high‐throughput nozzle‐free electrospinning process. Zinc oxide (ZnO) nanoparticles were robustly anchored to the PVDF‐TrFE EFs, assisted by a self‐polymerized polydopamine (PDA) layer, and subsequently grown into ZnO nanowires (NWs) using a low‐temperature hydrothermal growth method. The EF mats were investigated for active impact force transduction and the piezoelectric voltage outputs of different combinations of PVDF‐TrFE and ZnO nanomaterials were compared using two different impact force testing setups. The horizontal impact force test saw an increase in force sensitivity by a factor of 2.5 for the nanowires compared to the unmodified PVDF‐TrFE EFs. Similarly, vertical drop impact testing demonstrated a 5.8‐fold increase in sensitivity with a linear response (R2 = 0.986) for a large range of impact forces up to 970 N. The EFs were also tested as a wearable impact force sensor to quantify soccer ball heading force, which was measured as 291.3 ± 51.0 N for a vertical ball speed of 7.8 ± 1.5 ms−11 with an 8.2% average error compared to theoretical force values. It is believed the enhanced piezoelectric performance of these materials could provide a useful platform for wearable sensing and energy harvesting.