A study on electroactive PVDF/mica nanosheet composites with enhanced γ-phase for capacitive and piezoelectric force sensing

Herein, a multifunctional poly(vinylidene fluoride) (PVDF)/mica nanosheets composite (PMNC) thin film was developed for the capacitive and piezoelectric force sensor. High electroactive γ-phase content (89%) of PVDF was achieved through a facile rapid cooling process of PMNC films. The crystallinity of PVDF decreased upon the addition of mica nanosheets, while the dielectric constant increased significantly (~300 %). The capacitance-based PMNC pressure sensor was found to be sensitive to the applied pressure. On the other hand, the piezoelectric voltage of 18 V (single layer) and 32 V (multi-layer) was generated for PMNC loaded with 1% mica nanosheets. Furthermore, PMNC based nanogenerator generated a power density of 8.8 μW/cm2 and showed excellent durability (>60,000 cycles). High flexibility, lightweight and skin-friendly PMNC could be a potential material in applications such as energy harvesting, energy storage, actuators, self-powered and smart wearable electronic devices.