Investigation of 2D-Ti₃C₂T_X-Loaded PVDF Composites for a High-Performance Flexible Piezoelectric Energy Harvester and Wearable Sensor

Flexible piezoelectric generators have attracted a great deal of attention recently for their promising applications in mechanical energy harvesting and portable electronic devices. The significant properties of 2D MXene (Ti 3 C 2 T X ) inspired us to develop a nanocomposite with poly(vinylidene fluoride) (PVDF) by varying the Ti 3 C 2 T X filler using tape casting techniques. The structural and microstructural properties of the composite film were examined through X-ray diffraction and field-emission scanning electron microscopy. FTIR studies revealed that an increase in the electroactive phase from 73 to 82% was observed by adding the Ti 3 C 2 T X filler into the PVDF matrix. The frequency-dependent dielectric constant, dielectric loss, and RT impedance spectra were studied. The leakage current density and ferroelectric behavior of the Ti 3 C 2 T X -added PDVF composite films showed significant results as compared to the pure PVDF film. A bipolar strain with an electric field (S–E) curve was used to investigate the reverse piezoelectric coefficient (d 33 *). The piezoelectric response of the Ti 3 C 2 T X -added PDVF composite films showed a significant enhancement of the output power density (56.9 μW/cm 3 ) in comparison with that of a PVDF-based piezoelectric generator having a power density of 5.6 μW/cm 3 . Finally, the flexible piezoelectric generator was employed to efficiently detect human body movements as a self-poled wearable sensor and self-powered device.