Recently, Mxene-a new family of two-dimensional (2D) transition metal carbides and nitrides or carbonitrides (Ti₃C₂T_x) is gaining much attention as an effective filler to improve the dielectric property of the polymeric materials owing to its high negativity and good conductivity. Compared to other 2D materials, MXene has several advantages including metallic conductivity, high charge carrier mobility, diverse surface chemistry, tunable bandgap, and mechanical properties. Accordingly, 2D material composites including MXene, are being widely used in many different applications such as energy storage, flexible electronics, photocatalysis, biosensors, and gas sensors owing to its high conductivity and electronegativity due to the abundance of -F groups and terminating functional groups containing oxygen on it.

In this work, the metallic MXene (Ti₃C₂T_x) nanosheets are doped into the PVDF matrix followed by the standard electrospinning process to fabricate the PVDF/MXene composite (PMC) nanofibers, and the contribution of MXene on boosting the triboelectric energy harvesting performance of PVDF nanofiber is evaluated for the first time. The enhanced dielectric property of PMC nanofibers owing to the charge accumulation resulting from the macroscopic dipole formations, which contributes to the surface charge density, is utilized to investigate the triboelectric performance of the PMC nanofiber. The PMC nanofiber with different loading weight percentages (0, 5, 10, 15, 20, and 25) of MXene are fabricated and tested. The influence of the MXene loading into PVDF on its dielectric property, surface charge density, and on the electrical performance are evaluated for various MXene concentrations. As developed PMC nanofiber is paired with a highly positive Nylon 6/6 nanofiber to fabricate the TENG on a flexible Kapton substrate and it is characterized under gentle impact motions at varying frequencies and forces. The energy harvesting capability of TENG is evaluated and demonstrated by capacitor charging and by operating the low power electronics such as sport watch (timer), thermohygrometer sensor, and more than 120 commercial red LED's. Furthermore, the high level of mechanical durability and output signal stability has been verified for the as-fabricated PMC nanofiber and the TENG. Besides energy harvesting, TENG is also demonstrated as a self-powered motion sensor that can automate the step lights based on the human foot motion over the stairs.