Boosting piezoelectric output performance of composite flexible piezoelectric nanogenerators via incorporation of MXene

Improving the charge conduction ability of piezoelectric fibers can achieve high output performance of wearable piezoelectric nanogenerators (PENGs). In this paper, a 2D conductive carbon material, MXene, was added to the nanofiber film to obtain BT@F/MXene/PVDF PENG. MXene possess good electrical conductivity that can enhance the local electric field of piezoelectric fibers during the electrospinning process. This led to the enhanced piezoelectric properties of the BT@F/MXene/PVDF piezoelectric fibers. The β phase content and d 33 value of the prepared BT@F/MXene/PVDF piezoelectric fibers reached up to 95% and 48.7 ± 3 pC/N, respectively. Therefore, the electrical output performance of the prepared BT@F/MXene/PVDF PENG was significantly improved. The output voltage of the BT@F/MXene/PVDF PENG was measured to be 4.9 V, which was about 2 times higher than of the BT@F/PVDF PENG. We further analyzed the mechanism by which MXene improved the electrical output performance of PENG. Furthermore, we compared the 2D MXene with conductive carbon materials of other dimensions (0D carbon black and 1D CNT), which revealed that the BT@F/MXene/PVDF PENG exhibited the highest piezoelectric output performance. Thus, a PENG exhibiting high piezoelectric output was developed in this work through the synergistic enhancement effect of BT@F nanoparticles and 2D MXene. This device is suitable for various applications, including mechanical energy harvesting, motion monitoring, and power supply equipment. • MXene is used as 2D carbon material to enhance the piezoelectric properties of MXene/F@BT/PVDF composite PENG. • The 2D MXene was compared with conductive carbon materials of other dimensions (0D carbon black and 1D CNTs), and to explore the mechanism of MXene enhancing composite PENG. • The MXene/F@BT/PVDF composite PENG was sensitive to sense human motions, demonstrating its potential applications in wearable devices and sports monitoring.